The Middle East was a main focus here this year. Among other developments, the Iran nuclear deal, the ongoing Syrian civil war (including the question of strategy against ISIS), and the resurgence of violence on the West Bank (engaged in by both sides though conditioned by the seemingly now-permanent occupation) received some attention. The four guest posts by Peter T. were a highlight: see here, here, here, and here.
Other posts from this past year perhaps worth mentioning include a note about Machiavelli and mercenaries and a reflection on 'critical junctures'.
Finally, thanks to the readers and commenters whose contributions produced some good comment threads in 2015.