†Many people have gone far beyond the call of Rawlzickian duty in debating the themes of this article with me. I am especially grateful to fellow Fellows of Yale's Global Justice Program, the most stimulating and friendly work environment I have had the fortune to take part in. I presented an earlier draft at the Program's workshop (April 2012), where participants asked a variety of probing questions, and later benefited from many exchanges with Tom Andreassen, Daniele Botti, Markus Labude, Rob Lepenies, Christian Siller, Gilad Tanay and (in particular) David Ewert. At key junctures, Chris Armstrong, Tommaso Bardelli, Eric Beerbohm, Miri Bentwich, Burke Hendrix, Pablo Kalmanovitz, Lizzie Krontiris, David Miller, Eric Nelson, Cameron O'Bannon, Paulina Ochoa, Govind Persad, Dan Philpott, Ian Shapiro, Annie Stilz, Kok-Chor Tan, Matt Vermaire, Daniel Viehoff, Ernesto Verdeja, Paul Weithman, Leif Wenar, Lea Ypi, and Michael Zuckert helped me (sometimes unknowingly) see the need to move certain ideas to the fore and others to the background. Bob Goodin and four anonymous reviewers for The Journal of Political Philosophy did so very knowingly, and their comments on multiple versions significantly improved the final product. So did critical feedback from Thomas Pogge, who, with a typical combination of joviality and stern criticism, supervised this article from its inception to completion.