There may well be terror threats, but there are lots of countries beyond Afghanistan that harbor terrorists and we can't occupy all of them. Even before the withdrawal, we didn't occupy all of Afghanistan any more. I'm sure there is some impairment because of loss of eyes on the ground, but we would still need to be on watch even without withdrawal.

So I'm still not convinced the withdrawal was wrong, especially since there would be other risks of Russian mischief and limitations on supply to our forces if we were still operating there. Didn't Al Qaeda just move to Yemen (which we don't occupy) when we were in Afghanistan?