France's Charles de Gaulle aircraft carrier will be deployed to support operations against Islamic State in Syria and Iraq, November 18, 2015.
Jean-Paul Pelissier / Reuters

As France intensifies its airstrikes against the Islamic State (or ISIS) in Syria after the November 13 terrorist attacks in Paris, the question of when to intervene—that is, to forcibly come between another government and its subjects—is once again pertinent. We’ve dealt with this question before. Think of Russia and the United States as they began to arm their allies and intervene in Syria; or France, the United Kingdom, the United States, and other NATO allies in Libya in 2011; or, the failure to intervene in a timely or sufficient manner in Rwanda in 1994 or in Bosnia before 1995.


This article is part of our premium archives.

To continue reading and get full access to our entire archive, you must subscribe.