New Petro‐aggression in the Middle East: Saudi Arabia in the Spotlight

That hydrocarbon abundance may lead to more violence is an established truism in the literature on the resource curse. Looking at the Middle East, however, the literature relates bellicose state behaviour entirely to oil-producing revolutionary republics. Instead, dynastic monarchies are claimed to be the more peacefully behaving actors. Current developments turn this conclusion upside down, however. Since 2015 at the latest, the foreign policy of Saudi Arabia, the leading monarchy in the Middle East, has transformed from multi-dependence to petro-aggression. By discussing this striking transformation, the paper puts forward a framework looking at the interaction of three crucial dimensions: first, the decreasing power projection towards the Middle East by the United States, the decade-long hegemon, due to gradual changes in world energy markets and war fatigue at home; second, the lasting fiscal potency of the Saudi regime; and, third, the personalization of the Saudi monarchy under King Salman as a historically contingent result of transferring power to the generation of Ibn Saud’s grandsons. Policy Implications • Prepare sanctions for immediate reaction targeting those decision-makers from Saudi Arabia or other highly personalized political regimes being responsible for the emergence of new petro-aggressions. • Consider a global moratorium on all arms exports to every party in the Persian Gulf being involved in war-like events as a mid-term containment of new petro-aggressions. • Establish a robust regional security organization which should enclose all countries located in the broader Middle East as a long-term strategy to contain new petro-aggressions. • Improve policy coordination by creating regular policy consultations between those Asian and European actors, who would suffer most from the looming consequences of military escalation in the Straits of Hormuz and Bab al-Mandab. Saudi foreign policy transformation: from multidependence to petro-aggression Roughly until the late 1950s, Saudi Arabia was relatively inactive in regional politics. After having conquered the central parts of the Arabian peninsula by force based on a Bedouin army, Ibn Saud’s – the Kingdom’s ruling monarch – main concern was ‘to consolidate a territorially and socially expanding habitat and thereby to become an Arab state equal in scope with the Arabian peninsula’ (Sullivan, 1970, p. 436). The Saudi Kingdom started to emerge as a regional leader of the group of Middle East conservative monarchies in the early 1960s only, trying to oppose the waves of Arab nationalists’ rhetoric and actions led by the at that time Egyptian president Gamal Abdel Nasser and other pan-Arab republican politicians. Einkreisung – the myth of threatening encirclement – became a major concern, shaping Riyadh’s foreign policy ever since. This factor was also at the heart of the Kingdom’s key overall foreign policy strategy of stabilizing the regional system’s equilibrium by maintaining its existing balance of power (Sullivan, 1970). Based on that perspective, Saudi Arabia has been depicted as an omni-balancer, trying to counterweight between threats and challenges at the global, the regional as well as at the national level simultaneously. Nonneman (2005), for instance, argues that the Kingdom developed a strategy of managed multi-dependency as its main foreign policy preference. Or put differently, as Aarts (2007) has made clear, Saudi foreign policy maintains polygamous relations while walking a tightrope. Being interested in the domestic long-term power maintenance of the ruling Al Saud family, the two major foreign policy goals of the Kingdom have been to prevent the emergence of clear hegemons in the broader Middle East as well as to maintain the Saudi claim to a hegemonic role on the Arabian Peninsula by ‘asserting the right to be the dominant foreign partner for Yemen and the smaller monarchical states that with it make up the Gulf Cooperation Council’ (Gause, 2002, p. 196). As for conflict behaviour, based on a leadership style that was generally risk-averse Riyadh mostly avoided the initiation of direct interstate conflict (Nonneman, 2005). The language articulated towards the regional and international realms was generally modest and conflict-avoiding, the Kingdom trying to use its unique hydrocarbon wealth in order to buy out potential conflict instead. As highlighted Global Policy (2020) 11:1 doi: 10.1111/1758-5899.12780 © 2020 The Authors. Global Policy published by Durham University and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Global Policy Volume 11 . Issue 1 . February 2020 93 SpeclSection A ricle by Colgan (2013, p. 225), ‘Saudi Arabia’s foreign policy is marked by two themes: the incentives for international cooperation generated by oil, and the check-book diplomacy made possible by oil income’. Remarkably, the Arab Spring – a wave of mass uprisings in the Middle East and North Africa, which would spread throughout the wider region from December 2010 – led to several regime breakdowns among Arab republics, but not among the monarchies in the region (Lucas, 2014). It was also the starting point for civil wars in Libya, Syria and Yemen; its consequences induced a noticeable readjustment of Saudi foreign policy too. As most analysts would probably agree, Riyadh’s foreign policy decisions have since become much more assertive – with an offensive, if not even outright aggressive, undertone (e.g. Beck, 2016; Ragab, 2017; Richter, 2014). Since 2011, for the Kingdom the preservation of monarchical rule in the broader Middle East has become crucial by actively framing ‘the discourse around ongoing revolutions in sectarian terms, largely viewing transformations in the region through the lens of its regional competition with Iran’ (Ennis and Momani, 2013, p. 1128). The period between 2011 and the accession of Salman bin Abdulaziz to the Saudi throne represented, however, only the precursor towards an even more distinct, now truly bellicose and therefore substantial turn in Saudi foreign policy. Two events illustrate this historical shift. First, on 26 March 2015, Saudi Arabia – formally together with a number of partners but in fact taking on the main burden of responsibility via its own military forces, at least during the first days of the offensive – started to wage war on a coalition in northern Yemen led by the Houthi movement. Although this was not the first time the Saudis would deal with the Houthis militarily – a previous incursion into Yemeni territory occurred in November 2009 and continued until early 2010 as a response to Houthi forces ambushing Saudi border posts – previous Saudi engagement had never been as comprehensive as it was in the spring of 2015. Based on series of intense air strikes later supported by ground forces, Riyadh attempted to contain the growing influence of the Houthi movement, which a few days earlier had taken the Yemeni capital, Sana’a. Operation Decisive Storm, as it was officially named, represented the first step in a currently still ongoing state of military escalation at the southern end of the Arabian peninsula. So far, the Saudi–Yemen war has cost thousands of Yemenis their lives and led to an unprecedented aggravation of the humanitarian situation in the country. From a historical perspective, the ‘[Saudi] intervention was a sharp departure from the Kingdom’s habit of arming others while keeping its own forces in the barracks’ (Benjamin and Simon, 2019). As became clear from numerous media reports in the first half of 2015, it was the young prince and son of the king, Mohammad bin Salman (at that time two months into being Saudi minister of defence), who was leading this military campaign (Staff writer, 2015; e.g. Kerr, 2015). Second, on 5 June 2017, Saudi Arabia and Bahrain cut diplomatic ties, closed off borders, and issued travel bans from and to their neighbour Qatar. Over two weeks later, the now coalition of four – the United Arab Emirates and Egypt had joined this boycott a few days after it began – presented Doha with a list of 13 demands to be fulfilled, otherwise unspecified consequences would follow (Wintour, 2017). The demands were so high that compliance with them would have meant the end of an independent foreign policy for Qatar. Again, valid indications exist that this final escalation of a decade-long simmering feud between Saudi Arabia and Qatar has been decisively pushed by the personal decisions of Mohammed bin Salman (e.g. Coughlin, 2017) – motivated, as experts on monarchical regimes have argued, by the desire to secure his own succession to the Saudi throne (Lucas, 2017). In February 2018, the Qatari minister of defence accused Saudi Arabia and the UAE of having prepared for an invasion during the June 2017 crisis (Weymouth, 2018). Over a year later, in the summer of 2018, investigative journalism confirmed that suspicion – highlighting that in early June 2018, a military confrontation between several members of the GCC was only prevented by the intervention of then United States secretary of state Rex Tillerson (Emmons, 2018). Beyond the Saudi intervention in Yemen and the Qatar crisis – two ongoing events that clearly qualify as militarized interstate disputes according to standard definitions in peace and conflict studies (Maoz et al., 2019) – a number of previously unseen incidents also took place. These testify further that Saudi foreign policy behaviour has now substantially transformed. Among them are: 1. unprecedented diplomatic feuds with Western countries • After criticism by the Swedish foreign minister, Margot Wallstr€ om, in early 2015 with regard to the human rights situation in Saudi Arabia and the unilateral termination of the decade-long weapons memorandum with Riyadh by Stockholm a few weeks later, the Saudi ambassador was withdrawn. Riyadh lodged a formal protest, accusing the minister of ‘flagrant interference’ in Saudi internal affairs. • Due to the remark that ‘adventurism’ had spread throughout the region, made by former German foreign minister Sigmar Gabriel in November 2017, Riyadh recalled its ambassador to Germany, with medium-term consequences for German businesses – being afterwards excluded from public procurement. German–Saudi relations would only normalize again 10 months later, under current head of the German federal foreign office Heiko Mass in September 2019. • In August 2018, Saudi Arabia announced a number of far-reaching economic sanctions on Canada and expelled the Canadian ambassador from Riyadh due to a statement released by the Canadian minister of foreign affairs, Chrystia Freeland, via Twitter. In her tweet, Freeland expressed concerns about the recent imprisonment of Samar Badawi, a Saudi human rights activist and sister of the prominent blogger Raif Badawi, who has been behind bars since June 2012. © 2020 The Authors. Global Policy published by Durham University and John Wiley & Sons Ltd. Global Policy (2020) 11:1 Thomas Richter 94

Roughly until the late 1950s, Saudi Arabia was relatively inactive in regional politics. After having conquered the central parts of the Arabian peninsula by force based on a Bedouin army, Ibn Saud'sthe Kingdom's ruling monarchmain concern was 'to consolidate a territorially and socially expanding habitat and thereby to become an Arab state equal in scope with the Arabian peninsula' (Sullivan, 1970, p. 436). The Saudi Kingdom started to emerge as a regional leader of the group of Middle East conservative monarchies in the early 1960s only, trying to oppose the waves of Arab nationalists' rhetoric and actions led by the at that time Egyptian president Gamal Abdel Nasser and other pan-Arab republican politicians. Einkreisungthe myth of threatening encirclementbecame a major concern, shaping Riyadh's foreign policy ever since. This factor was also at the heart of the Kingdom's key overall foreign policy strategy of stabilizing the regional system's equilibrium by maintaining its existing balance of power (Sullivan, 1970).
Based on that perspective, Saudi Arabia has been depicted as an omni-balancer, trying to counterweight between threats and challenges at the global, the regional as well as at the national level simultaneously. Nonneman (2005), for instance, argues that the Kingdom developed a strategy of managed multi-dependency as its main foreign policy preference. Or put differently, as Aarts (2007) has made clear, Saudi foreign policy maintains polygamous relations while walking a tightrope. Being interested in the domestic long-term power maintenance of the ruling Al Saud family, the two major foreign policy goals of the Kingdom have been to prevent the emergence of clear hegemons in the broader Middle East as well as to maintain the Saudi claim to a hegemonic role on the Arabian Peninsula by 'asserting the right to be the dominant foreign partner for Yemen and the smaller monarchical states that with it make up the Gulf Cooperation Council' (Gause, 2002, p. 196).
As for conflict behaviour, based on a leadership style that was generally risk-averse Riyadh mostly avoided the initiation of direct interstate conflict (Nonneman, 2005). The language articulated towards the regional and international realms was generally modest and conflict-avoiding, the Kingdom trying to use its unique hydrocarbon wealth in order to buy out potential conflict instead. As highlighted by Colgan (2013, p. 225), 'Saudi Arabia's foreign policy is marked by two themes: the incentives for international cooperation generated by oil, and the check-book diplomacy made possible by oil income'.
Remarkably, the Arab Springa wave of mass uprisings in the Middle East and North Africa, which would spread throughout the wider region from December 2010led to several regime breakdowns among Arab republics, but not among the monarchies in the region (Lucas, 2014). It was also the starting point for civil wars in Libya, Syria and Yemen; its consequences induced a noticeable readjustment of Saudi foreign policy too. As most analysts would probably agree, Riyadh's foreign policy decisions have since become much more assertivewith an offensive, if not even outright aggressive, undertone (e.g. Beck, 2016;Ragab, 2017;Richter, 2014). Since 2011, for the Kingdom the preservation of monarchical rule in the broader Middle East has become crucial by actively framing 'the discourse around ongoing revolutions in sectarian terms, largely viewing transformations in the region through the lens of its regional competition with Iran' (Ennis andMomani, 2013, p. 1128). The period between 2011 and the accession of Salman bin Abdulaziz to the Saudi throne represented, however, only the precursor towards an even more distinct, now truly bellicose and therefore substantial turn in Saudi foreign policy. Two events illustrate this historical shift.
First, on 26 March 2015, Saudi Arabiaformally together with a number of partners but in fact taking on the main burden of responsibility via its own military forces, at least during the first days of the offensivestarted to wage war on a coalition in northern Yemen led by the Houthi movement. Although this was not the first time the Saudis would deal with the Houthis militarilya previous incursion into Yemeni territory occurred in November 2009 and continued until early 2010 as a response to Houthi forces ambushing Saudi border postsprevious Saudi engagement had never been as comprehensive as it was in the spring of 2015. Based on series of intense air strikes later supported by ground forces, Riyadh attempted to contain the growing influence of the Houthi movement, which a few days earlier had taken the Yemeni capital, Sana'a. Operation Decisive Storm, as it was officially named, represented the first step in a currently still ongoing state of military escalation at the southern end of the Arabian peninsula. So far, the Saudi-Yemen war has cost thousands of Yemenis their lives and led to an unprecedented aggravation of the humanitarian situation in the country. From a historical perspective, the '[Saudi] intervention was a sharp departure from the Kingdom's habit of arming others while keeping its own forces in the barracks' (Benjamin and Simon, 2019). As became clear from numerous media reports in the first half of 2015, it was the young prince and son of the king, Mohammad bin Salman (at that time two months into being Saudi minister of defence), who was leading this military campaign (Staff writer, 2015; e.g. Kerr, 2015).
Second, on 5 June 2017, Saudi Arabia and Bahrain cut diplomatic ties, closed off borders, and issued travel bans from and to their neighbour Qatar. Over two weeks later, the now coalition of fourthe United Arab Emirates and Egypt had joined this boycott a few days after it beganpresented Doha with a list of 13 demands to be fulfilled, otherwise unspecified consequences would follow (Wintour, 2017). The demands were so high that compliance with them would have meant the end of an independent foreign policy for Qatar. Again, valid indications exist that this final escalation of a decade-long simmering feud between Saudi Arabia and Qatar has been decisively pushed by the personal decisions of Mohammed bin Salman (e.g. Coughlin, 2017) motivated, as experts on monarchical regimes have argued, by the desire to secure his own succession to the Saudi throne (Lucas, 2017). In February 2018, the Qatari minister of defence accused Saudi Arabia and the UAE of having prepared for an invasion during the June 2017 crisis (Weymouth, 2018). Over a year later, in the summer of 2018, investigative journalism confirmed that suspicionhighlighting that in early June 2018, a military confrontation between several members of the GCC was only prevented by the intervention of then United States secretary of state Rex Tillerson (Emmons, 2018).
Beyond the Saudi intervention in Yemen and the Qatar crisistwo ongoing events that clearly qualify as militarized interstate disputes according to standard definitions in peace and conflict studies (Maoz et al., 2019)a number of previously unseen incidents also took place. These testify further that Saudi foreign policy behaviour has now substantially transformed. Among them are: 1. unprecedented diplomatic feuds with Western countries • After criticism by the Swedish foreign minister, Margot Wallstr€ om, in early 2015 with regard to the human rights situation in Saudi Arabia and the unilateral termination of the decade-long weapons memorandum with Riyadh by Stockholm a few weeks later, the Saudi ambassador was withdrawn. Riyadh lodged a formal protest, accusing the minister of 'flagrant interference' in Saudi internal affairs.
• Due to the remark that 'adventurism' had spread throughout the region, made by former German foreign minister Sigmar Gabriel in November 2017, Riyadh recalled its ambassador to Germany, with medium-term consequences for German businesses being afterwards excluded from public procurement. German-Saudi relations would only normalize again 10 months later, under current head of the German federal foreign office Heiko Mass in September 2019.
• In August 2018, Saudi Arabia announced a number of far-reaching economic sanctions on Canada and expelled the Canadian ambassador from Riyadh due to a statement released by the Canadian minister of foreign affairs, Chrystia Freeland, via Twitter. In her tweet, Freeland expressed concerns about the recent imprisonment of Samar Badawi, a Saudi human rights activist and sister of the prominent blogger Raif Badawi, who has been behind bars since June 2012. • In April 2019, it became know that Saudi Arabia helped pay for the operations of Khalifa Haftar, a Libyan warlord from the eastern part of the country, in order to try to take the country's capital, Tripoli.
• More recently, Riyadh had started to support the crumbling military regime in Sudan amid the rise of mass protests aiming at establishing a civilian government.

the persecution as well as execution of Saudi opposition members
• While there is increasing indication that opposition groups in exile have been under surveillance for years by Saudi government agencies, and anecdotal evidence exists that occasionally Saudi citizens have been deported 'to bring them home', on 2 October 2018 Jamal Khashoggia US-based journalist and previous member of the Saudi establishmentwas murdered by state agents in the country's consulate in Istanbul.
To conclude, a transformation has recently taken place in traditionally multi-dependent and cooperative Saudi foreign policy. Clearly, as many analysts have pointed out (e.g. Karim, 2017;Ragab, 2017;Yossef, 2018), an early starting point of this change can be traced back to the regional waves of protests running throughout the Middle East and North Africa between late 2010 and the second half of 2011. However, since King Salman's accession to the throne in January 2015, this foreign policy transformation has gained new momentumnow with a clearly aggressive and even bellicose dimension to it.
In order to understand this remarkable change, the paper puts forward a framework looking at the historical interaction of three crucial elements in order to explain the emergence of and continuity in Saudi petro-aggression: first, the decreasing power projection towards the Middle East by the US, the decade-long hegemon, due to gradual changes in world energy markets and war fatigue at home; second, the lasting fiscal potency of the Saudi regime due to the most recent hydrocarbon price hike; and, third, the recent personalization of the Saudi monarchythat is, the transition of what had been known to be a dynastic monarchy towards a personalistic and hence absolute monarchical system under King Salman. While the first two elements can be considered to be necessary conditions in order to explain the broader context in which the recent Saudi foreign policy transformation took place, the personalization of power within the Saudi monarchy itself is truly crucial in order to fully explain this substantial policy shift.

The waning nature of US foreign policy in the Middle East
Historically, the starting point of US interest in the Gulf region was clearly the strategic importance of crude oil, which became the main basis of energy production for all industrialized economies around the globe after World War II. In July 1933 a first concession was given to Standard Oil of California (SOCAL), a US company previously operating in Bahrain, in order to explore and produce crude in the Eastern Province of Saudi Arabia. This was the first step in a fruitful US-Saudi business relationship, which later turned into a close and strategic political partnership between the two countries. Middle Easternand as a main component of it, Saudioil was an indispensable source to fuel reconstruction and post-War development in Western Europethe world region that the US's security was inextricably tied to after 1945 (Bronson, 2005).
With the Cold War beginning to unfold and Soviet power starting to expand globally, the broader Middle East region gained enormous strategic importance for the US. In this context, the special significance of the Gulf region for the US was most prominently highlighted after the Islamic Revolution in Iran and the Soviet invasion of Afghanistan, as addressed by US President Jimmy Carter's state of the union speech on 23 January 1980: Let our position be absolutely clear: An attempt by any outside force to gain control of the Persian Gulf region will be regarded as an assault on the vital interests of the United States of America, and such an assault will be repelled by any means necessary, including military force. (Taylor, 1986, p. 156) The Carter Doctrine was the first and most explicit statement of a US security guarantee for the Gulf (Jeffrey and Eisenstadt, 2016). Securing access to and the free flow of Global Policy (2020) (2009-2017), a perception arose among the Arab Gulf countries that the US would not under any condition keep its historical promise of giving support and protection to its Middle East allies. One crucial event in this regard was the reaction of President Obama to the Egyptian revolution in early 2011, and the withdrawal of unconditional support for long-time friend President Mubarak. At that point, it became clear to Riyadh and the other Arab monarchies that 'the USA is unlikely to conduct a Cold War-style armed intervention to save the throne of an ally from its own people' (Partrick, 2016, p. 361). What later became known as the Obama Doctrine, a new defensive role for the US in the region, meant that if none of the US's vital national interests were directly concerned then 'the mobilization of partners and allies allows for the sharing of the strategic and operational burden' (Krieg, 2016, p. 97). Clearly, the refusal by the Obama administration to robustly sanction by means of military force the use of chemical weapons by the Assad regime in 2013despite its famous definition of this as a 'red line'as well as the successful negotiation of the nuclear accord with Iran in 2015 despite major hesitations on the part of close and long-time allies like Israel and Saudi Arabia exemplify the new strategic focus in US foreign policy towards the broader Middle East.
Two substantial structural elements help us to understand this most recent change in the nature of US foreign policy. First, during the 2010s US domestic politics has been marked by war fatigue with regard to the nation's engagement in the region due to the lengthy and costly military operations in Afghanistan since 2001 and Iraq since 2003. Politicians across the board have therefore called for less costly global US military engagement, with a special focus on the Middle East. This was particularly relevant during the period of austerity in the US emerging as a reaction to the global financial crisis of 2008. Second, the shale gas revolutionwhich many believe to be the greatest boom ever for the US economyhas significantly decreased the dependency of the US on the import of crude and refined oil products. As data from the U.S. Energy Information Administration signifies, import dependency has drastically reduced since the middle of the first decade of the new century; in 2017, the value of net imports was the lowest ever since data first became available (U.S. Energy Information Administration, 2019).
Based on the observation that the US, as the long-standing Gulf hegemon and despite recent redeployments of some troops to the Saudi Kingdom, has been pulling back from the Middle East as a whole and will very likely henceforth not try to penetrate the region as powerfully as it did in the past, regional actors now face a unique historical situation 'enabling them but also forcing them to fend for themselves. This marks a watershed for regional actors' security cooperation' (Sunik, 2018, p. 78). This need becomes even more acute given the lack of willingness or indeed capability vis-a-vis power projection by any alternative global or regional power. The absence of institutional incentives for mutual exchange and cooperation within the broader Middle East only accentuates this problem.

The fiscal potency of the Saudi monarchy
Income from hydrocarbon resources was historically and indeed still is the most important source of government revenue for the Gulf monarchies. Since the 1970s, on average hydrocarbon revenues have constituted over 50 per cent of state income in all of them. In Saudi Arabia, being the biggest oil producer in the region and one with a leading global role, this relative share was significantly higherand in many years above the level of 80 per cent (Richter, ). Since state revenues, and therefore almost all state activity, has been so dependent on hydrocarbon income, the Gulf monarchies have been labelled 'rentier states' (Beblawi and Luciani, 1987;Mahdavy, 1970).
Hydrocarbon income is both a blessing and a curse at the same time. It provides enormous room for fiscal manoeuvring on the one side. But it also, on the other, makes government budgets vulnerable to the ups and downs of hydrocarbon prices on international markets. After the oil price revolution of the late 1970s, which flooded the national budgets of the Gulf monarchies with vast hydrocarbon incomes up until the early 1980s, and the subsequent long-lasting low-price phase of hydrocarbon resources (starting during the mid-1980s and lasting until the late 1990s), a new high-price cycle began in the first years of the new centurylasting until 2014. 2 This second oil price revolution brought again enormous wealth to the Gulf region. While only rough approximations exist about the true values of the wealth accrued within Gulf monarchies during that latest period, a look at the accumulation of international reserves is considered to be a relatively valid proxy for the fiscal potency that some of the Gulf monarchies gained.

The personalization of the Saudi monarchy
Saudi Arabia is an authoritarian monarchy, with Wahhabi Islam the official religion. Since its self-declared independence in 1932, the country has been ruled by the Al Sauds a noble family originating from Nejd, one of the inner regions of the Arabian peninsula. The current Saudi king, Salman bin Abdulaziz, now in his mid-80s, is the oldest surviving son of the legendary founding father of the modern Saudi state, King Abdulaziz Al Saud. Ibn Saud, the name he became well known by in the West, used to be an absolute ruler legitimized by the century-old political alliance with the puritanical reform movement of Wahhabi Islam and by his personal reputation as a tribal sheikh and field commander during the conquest of the main parts of the Arabian peninsula by his forces after 1902.
After the demise of the nation's founding father in 1953, a distinct system of family rule and power sharing among a select group of his male descendants emerged. What started as shared rule between the two oldest sons of the late king -Saud as his father's immediate successor, and Faysal as heir apparentdeveloped into several rounds of intense inner-family feuds during the late 1950s and early 1960s, incorporating competing groups from among the most senior sons of Ibn Saud (K echichian, 2008). After more than five years of inner-family strife, Faysalsupported by those of his brothers who later became the core group of Saudi decision-makersoverthrew King Saud and took the throne in his place. This sequence of events eventually led to what later was described to be a dynastic monarchy (Herb, 1999) that is, a kind of rule by several core members of the royal family based on a system of separated domains which provided highly autonomous playing fields for each of the senior princes (e.g. Al-Rasheed, 2005; Hertog, 2010). The king, even though formally holding absolute power, was only the primus inter pares, and needed to make sure that a political decision was only reached after extensive consultation among senior princes. This system, quite in contrast to most of the personalistic dictatorships within other Arab states at the time, was often slow and inefficient, but entailed a strong notion of within-family deliberation about key policy issues (Karim, 2017). Based on the experience of the paralysing rivalry between Saud und Faysal during the late 1950s and early 1960s, to seek consensus and not feud within the family would become the guiding principle of Saudi foreign policy decisions until very recently.
Strikingly, with King Salman ascending to the throne in January 2015 a process of centralization would take place Saudi Petro-Aggression (Karim, 2017;Hertog, 2018;Benjamin and Simon, 2019). Eventually, this led to the abandoning of the traditional system of intra-family consensus-seeking. This process not only restructured the policy making cycle, rendering it less timeconsuming and hence making it more efficient, but also created a significant higher degree of personalization, leaving final decision-making in the hands of formally two menoften even only one man. This was Muhammed bin Salman, the favourite son of the new king, who in April 2015 became deputy crown prince and in June 2017 was promoted to be the next king of Saudi Arabia when his father passes away. Since early 2015, though, the previously established model of a dynastic monarchy has transformed into a system of a very personalized monarchy, thereby leaving decision-making exclusively with the king and his heir apparent. Two aspects are crucial to understanding this groundbreaking transformation and personalization of the Saudi policy making system. First, King Salman is the last from among the group of senior princes who have dominated the policy making of Saudi Arabia for decades (House, 2016;Al-Rasheed, 2018;Hertog, 2018). He was the governor of Riyadh, the Saudi capital, from 1963 to 2011 and belongs to the 'Sudairi seven'a powerful group of full-brothers among the sons of Ibn Saud. Salman early on became interested in politics, being a close follower of and advisor to his older full-brothers Fahd (king between 1982 and 2005), Sultan (long-time minister of defence and crown prince between 2005 and 2011) and Nayef (long-time minister of interior and crown prince between 2011 and 2012) (Wihbey, 1997). Historically, the Sudairi seven were crucial supporters of Faisal during the inner-family feud with King Saud in the early 1960s (K echichian, 2008). As a result of Faisal's accession to the throne, he promoted the Sudairi brothers to become key players in the consolidating Saudi state during a period of soaring hydrocarbon revenues. Strikingly, it was largely the fact that Salman was the only brother left from among the sons of Ibn Saud who decisively shaped the early consolidation of the modern Saudi state during the 1960s and 1970s which would, after the death of Abdullah in January 2015, provide him with a previously unseen autonomy as the new Saudi king to shape the future trajectory of the country under his tenure and according to his own personal preferences.
Second, the aspirations of King Salman's favouritebut not oldestson Mohammad, a young, self-confident and overly ambitious prince, equipped him with the instincts necessary to take the opportunity to prepare for his own accession to the throne after his father became crown prince in June 2012. Based on the few accounts which exist about Muhammed bin Salman, or MBS as he is often referred to, he already as a childbeing the oldest among his full-brothers -'went after what he wanted. The more often he got it, the more assured he became' (House, 2019, p. 18). The prince was mainly educated within Saudi Arabia, and became very close to his father by working together with him already at the age of 17. In the course of time, he was able to earn the deep trust and respect of his father. Positioned as the later king's closest follower and the head of his personal court, MBS profited immensely from his father's role as the governor of Riyadh and head of the Al Saud family (or Descendants Council). Young MBS began to stick to his father, soaking up how to deal with fractious tribal leaders, learning what princes were guilty of which indiscretions, sitting through the meetings his workaholic father had daily. All of this information later was put to use by the Crown Prince as he consolidated power against his royal relatives and subdued religious and tribal forces. (House, 2019, p. 9) On a more personal note, Prince Muhammedquite in contrast to the vast majority of the other male descendants of Ibn Saudseems to be an outstanding example of a risk-taker. 'His aides say he consistently opts for action over caution. The risk inherent in change, he tells associates, is less than the risk of doing nothing' (House, 2019, p. 15). How this personal trait might play out in real politics was confirmed by a leaked memo of the BND, the German foreign intelligence agency, in early December 2015. It assessed the new Saudi foreign policy as 'ready to take unprecedented military, financial and political risks in order not to fall into a disadvantageous position in the region' (Smale, 2015).
As has been rightly pointed out by leading experts on Saudi Arabia, one major consequence of the personalization of the Saudi decision-making system under the dominance of now crown prince Mohammad bin Salman is the expectation of a more assertive foreign policy (Kinninmont, 2015) and a generally 'larger appetite for risk than the consensusoriented previous leadership had' (Hertog, 2018, p. 89). However, an understanding of the necessary and therefore enabling conditions of the current shift in Saudi foreign policy behaviour would be incomplete without taking into consideration two additional elements. First, the nature of the contemporary Middle East policy of the USwhich for more than three decades represented the hegemonic power in the region, but who, as noted, has begun to redefine and adjust its role permanently therefore creating opportunities as well as necessity for single state action. Second, the legacies and opportunities of the Saudi rentier state, which makes available the enormous hydrocarbon revenues to be freely spent at the discretion of the ruler and his son. This is done by little in the way of additional institutional and social constraints to decision-making existing, especially in the realm of foreign policy. How these elements interact with each other, forming a historically unique constellation which has led to the emergence of Saudi petro-aggression, will now be discussed.

When does (new) petro-aggression emerge?
Jeff Colgan (2010Colgan ( , 2011Colgan ( , 2013 has highlighted that global oil consumption is a significant cause of international war. 'Under certain conditions, oil income enables aggressive leaders to eliminate political constraints, reduce domestic accountability, and take their countries to war' (Colgan, 2013, p. 1). Aggressive leadership, as he argues, arises in the context of domestic political revolutions, predominantly for two main reasons. First, revolutionary dynamics tend to favour risk-taking leaders, who aim at revising the status quo. Second, revolutions by definition eliminate existing institutional constraints that otherwise could have nullified risk-taking politicians. A combination of revolutionary leadership with high oil income creates an especially bellicose context. Oil exports facilitate risk-taking leaders if they are able to control respective revenues, which is invariably the case due to the unique nature of oil income being easily centrally controlled by a small group of political elitesor even a single actor. 'Yet a leader with huge financial resources to redistribute to purchase political support can afford to take risks, including those involved in aggressive foreign policy adventurism' (Colgan, 2013, p. 4).
As brilliant as this argumentation might be in explaining the warfare of Iraq under Saddam Hussein, Libya under Muammar Qaddafi, Iran under the Islamic regime and the aggressive regional ambitions of Venezuela under Hugo Ch avez (four oil states with clearly different revolutionary regimes), Colgan's approach is by and large unsuited to making sense of the most recent Saudi foreign policy transformation however. The Saudi Kingdom being an oil exporter par excellence does not mean it has ever been a revolutionary regime. The rise of Saudi petro-aggression, as outlined above, is even more puzzling when it is pointed out that the historical evolution of Saudi foreign policy is used by Colgan (2013, p. 56) as an important contrasting example for demonstrating the cooperative incentives which arise from producing crude oilwith it helping 'to avoid international conflict which interrupts export sales and other economic links'. What, therefore, are the relevant factors and combinations of them that might explain the surprising turn towards a bellicose foreign policy by Saudi Arabia after 2015, an oil exporter previously considered to be largely cooperatively embedded in world politics? I suggest three interacting elements worth considering in this context. First, the continuous availability of fiscal resources stemming from oil revenues allows for the socially unconstrained and intensified development of military capabilities. This new military strength can then be used to deter external threats, to proactively prevent emerging challenges or to expand a given country's own influence and power throughout its region. The rise of military spending in Saudi Arabia, as discussed above, testifies to the relevance of this development against the backdrop outlined in this paper.
Second, the stepping back by a hegemonic power within the framework of a fragmented regional systemone in which no robust regional security cooperation organization existsis especially prone to generating instability. The rising propensity for military conflict can be expected for two different reasons: (1) emerging or aspiring regional powers will exist in direct contrast with each other; and (2) no regional crisis management or security institutions are in place, meaning regional actors are left alone with crisis prevention and management. As a result, for each member of the regional state system the incentives to preserve their own individual security above all else increase. As laid out in detail earlier, the Obama Doctrine and subsequent US foreign policy towards the Middle East can be interpreted as having signalled the intention by that country to genuinely Global Policy (2020)  disengage from the Middle East. Consequently, regional as well as extra-regional actors have started to become increasingly active in regional affairscausing intense competition, and with it the rise of violent tensions within the region. Both the latent fiscal potency based on the past and continuing flows of oil income, which enable domestically unconstrained petro-dollar recycling in order to catch up militarily, have in combination with the regional-level condition of heightened insecurity and fragmentation provided the necessary structural incentives (or conditions) for some oil-exporting monarchies to increasingly consider military action a valid means of resolving competing foreign policy goals. However it is, third and most importantly, the rise of risk-taking leaders at the national level that makes this structural constellation especially dangerous. MBS, current Saudi crown prince and the person most likely to become the next king, represents this category masterfully. A general personality attribute of not being afraid of taking risks, together with his pronounced will to become the next Saudi king, has since 2015 led to an unprecedented personalization of decision-making within Saudi Arabia's recent history. Similarly, as described in the existing literature on petro-aggression looking at oil-exporting revolutionary regimes, Saudi oil income has significantly helped to facilitate the current process of centralizing power in the Kingdom. As recent research on the emergence of the Public Investment Fund (PIF)the sovereign wealth fund of Saudi Arabiahas shown, PIF has become a major tool developed and used by the crown prince in order to increase his grip on power by controlling fiscal and economic activities both within Saudi Arabia and abroadundertaken ultimately in order to prepare for his accession to the throne (Roll, 2019).
The larger consequences of this historical conjunction of these three elements are wholly depressing. As a close follower of the crown prince's ascension has noted: 'If his short history is any guide, there is little likelihood of major changes in the Crown Prince's character or style' (House, 2019, p. 18). Also little prospect exists that the US's current Trump administration will discontinue the broader policies laid out in the Obama Doctrine, with the only exception being that Iran is now seen as the greatest threat across the broader Middle East and Saudi Arabia has emerged as a critical partner 'in our efforts to advance regional stability' (Polaschik et al., 2019, p. 8). Against the general background context discussed in this paper, this means a 'dangerous region is getting more volatile' (Riedel, 2017). Or, summarized, more bluntly: 'Mohammed bin Salman, if allowed to ascend to the throne without facing any consequences from Washington for his outrageous behavior, will likely terrorize the region for decades, just as Saddam did' (Toossi and Costello, 2018).
While besides targeted sanctions few immediate possibilities are left for policy makers to shape this constellation, there are two broaderboth medium-and long-termstrategies to work on at least. First, a global moratorium on arms exports should be establishedone which has to include all parties in the Persian Gulf involved in war-like events. As the cynical support of the US and UK during the Yemen war of the last years has shown, Arab monarchies' warfare capabilities are critically dependent on Western support. Cutting off this support could reduce the likelihood of war being actively waged in the region.
Second, and as a long-term policy commitment, Asian and European powers have to heavily invest in the establishment of a robust regional security organization for the broader Middle East including all countries situated in the region. The looming consequences of military escalation in the Straits of Hormuz and Bab al-Mandab, leading to the potential interruption of crucial trade routes, will be extremely costlyespecially for European Union members states as well as for a number of East, South and Southeast Asian countries. Policy makers from these countries should therefore be particularly interested in helping contain future petro-aggression within the Middle East.

Notes
The author thanks Martin Beck, Morten Valbjørn, Ray Hinnebusch, one anonymous reviewer, discussants at the 2018 international conference 'The Middle East and North Africa in an Age of Continuous Crisis, Conflicts, and Cracks' at the University of Southern Denmark (SDU), and the editor of the journal for their feedback.