Do you think it is a safe assumption that I can carry a manual pocket knife with a cutting edge under 3" without trouble while visiting multiple states and DC? I also thought about leaving the knives at home and just carrying my LM Wave, but I could potentially (though I don't see any reason I'd be having a run in with the police) get in trouble because of the blade length I think. I asked the question this way because it seems that in general 3" is the rule. I know that if I do visit any federal buildings while in DC I can't take any blades. Any help is appreciated!