I think it depends on the quality of the nation-building that happens afterwards.
Why would the answer be any different from "the usual"..?
militarily defeating IS counts under the "benefits" column of the analysis - as a pure point of rationality - even if the cost is too great.
True. And just as true for North Korea.
And just as true for North Korea.
ISIS doesn't have nukes and isn't being implicitly backed by a neighboring superpower.
Here's my op-ed that uses long-term orientation, probabilistic thinking, numeracy, consider the alternative, reaching our actual goals, avoiding intuitive emotional reactions and attention bias, and other rationality techniques to suggest more rational responses to the Paris attacks and the ISIS threat. It's published in the Sunday edition of The Plain Dealer, a major newspaper (16th in the US). This is part of my broader project, Intentional Insights, of conveying rational thinking, including about politics, to a broad audience to raise the sanity waterline.