The government and especially the military makes plans of all sorts. Those plans can be used to estimate the posiblity of such plans being used and their success. There are plans for invasions of every country in the world, including allies. There are plans for defense against every concievable type of attack. This is standard in the government and whole departments are dedicated to just these sorts of things. You can bet its all been upgraded considerably since 9/11.
Northwoods is probaly a old such plan from the 60's. Makes me wonder why they would remove the classification from such a thing.
When I die I'm sure to go to heaven, cause I spent my time in hell.
You get more with a kind word and a two by four, than you do with just a kind word.