I would have to say "Not without just cause for the specific case, and a warrant."

I say "No" to fishing expeditions where they hope to catch something as they listen to hundred or thousands of conversations.
I say "Yes" to wire-tapping where it involves someBODY (not just ANYbody who happens to be talking to anybody in a foreign country) who is a suspected terrorist.

I think this article makes plain that they're on a fishing expedition with no clue as to whether they'll catch something...