In September 2014 the people of Scotland will vote on whether to become an independent nation, with the defence and security of Scotland proving to be one of the more vociferous areas of debate. This article argues that defence and security implications of this referendum are far more fundamental than either the ‘yes’ or ‘no’ campaigns have admitted. It makes four points. First, it suggests that the Scottish government's plans for defence and security in NATO and the EU are at odds with its proposed armed forces and that Scotland may well find itself having to make far greater commitments to defence to assure its allies. Second, it argues that a vote for independence will represent a game-changing event for the remainder of the United Kingdom's defence and security, which will have significant consequences for the United Kingdom's partners and allies in NATO, the European Union and elsewhere. Third, the article contends that even a vote against independence will have a long-term impact, in that the ‘West Lothian question’ and Scottish support for nuclear disarmament influence the 2015 Strategic Defence and Security Review. Finally, the article highlights how this issue has revealed weaknesses in the think-tank and academic communities, particularly in Scotland. The independence vote does, therefore, represent ‘more than a storm in a tea cup’ and thus there needs to be far greater engagement with these issues within the United Kingdom and elsewhere.