I hope you'll read it, but just in case here is the Executive Summary:
1. It has become far too cheap and easy for the United States to begin bombing or drone-attacking other countries.
2. In the long run, this almost never works out well, even when the original rationale for "doing something" seems compelling, as with Syria.
3. Thus there should be a very strong burden of proof on people calling for strikes, to show that this is the only answer (not just the easiest one), and that it will do more good than harm. I will resist proposing that the burden of proof be doubled for people who recommended war in Iraq.