The Executive Branch can authorize surveillance - I don't see anyone arguing otherwise. There is, however, a law that must be followed. That doesn't mean that surveillance can't happen, but that such surveillance is conducted according to the law (FISA). In this particular case, even if US persons were involved, I haven't heard or read anything that would lead me to believe that FISA wasn't followed.

It's ironic that you would use the phrase "utter stupidity." FISA doesn't say to get a warrant after something has happened (like a bombing); it says that a warrant may be requested after the surveillance has already started. If a determination is made that an emergency situation exists, surveillance may be authorized without a court order for up to 72 hours - i.e., a warrant may be issued "after the fact" of the surveillance being authorized and in place. In addition, the President can authorize surveillance for the purpose of obtaining foreign intelligence for up to one year without a warrant, as long as certain conditions are met, including that no US persons are involved.