Biden : "Does the president have the authority to invade Iran tomorrow absent the ability to show there is no immediate threat to our national security?".
Yes. He is the Commander in Cheif.
Considering the fact that the Congress has been pretty much shut down because of partisanship...
President Bush would be derelict in his duties..if he DID wait for approval at this point!!
I can't imagine almost any scenario that Biden, Levin, Kennedy, would EVER give Bush "permission" to go to war.