Let us pretend that the W.H.C.L. (The We-Hate-Canada-League) started launching attacks from Maine into Canada.
It would be the United States that is criticized.
The US has the responsibility to control the elements in its country with internal police work. The same with Lebanon.
Hmmm...
At the same time, would you feel that Canada destroying airports in Maine would encourage you to control the WHCL?
Even if you werent much of a fan of the WHCL, you may be excused for starting to feel... a bit WHC yourself?
Thus, Canadas actions wouold be counterproductive?
Much better if Canada didnt bomb your airport, and worked with you to deal witj WHCL... JMO