I myself have no problem with being warned that there is a threat to America, but if it's real, by all means, why not TELL US WHAT THE THREAT IS?
Will that too EMBOLDEN, our enemies. I really don't see how it would, do you? Heck it might make them less effective don't you think? Many eyes being overall better to watch for terror than just a few.
But isn't it amazingly convenient that the government can just declare today "orange", scare the living crud out of everyone, and pass the patriot act or renew it? Or decide to wire tap someone's phone? Or engage in a little light Geneva Convention flouting? No details necessary, no questions asked, no evidence provided.
Living in fear when you are under attack is justified. Living in nebulous, never ending fear of some impossible to track or identify shadowy enemy who may or may not be there at all is not.
Terrorists decided to attack us, and it was a horrible thing. Many lives were lost in a tragedy no one anticipated. Did we need to review national security, yes. Should we have let it turn America into a country of people so frightened that we allow the likes of GWB to subjugate us, unquestioning, to his will? NO.
You cannot be totally safe in a free country, and you can never be free in a totally safe country either. It's a choice.