The real threat lies with the couple of thousand operatives who have already passed through the training camps, infiltrated our country and set up shop.
I don't believe any of it. They will hit when they want, in ways that are either so obvious or diabolical that we have no defense.
If you see somebody taking pictures of a nuclear plant, or a dam, or an airport (or any other strategic facility), well, act on it! Don't stop and worry about being sensitive to the guy's skin color, for Christ's sake!
(And I'm worried about Canada, too. Seems Canada is a real liberal haven for all sorts of ME cells...)