That's all well and good, but tell what's the risk in getting a warrant when one of the parties is in the U.S.? It's not like the the FISA courts are particularly hard-line on issuing warrants.
Intelligence agents have said the warrant process can take hours. You need quick action on the ground for the intercepts on the ground sometimes.
The law lets bush do this. People that want to risk intelligence for a warrant when the law allows bush to do this are falling into the clinton trap.
Clinton made everything a EU legal matter. Do we want arlen specter's scottish laws making decisions or brave cia agents on the ground acting on real time intelligence.