Even with that power, Congress hasn't formally declared war since World War II.
Every subsequent conflict involving U.S. forces, including military conflicts in Korea, Vietnam, Panama, Iraq, the Caribbean island of Grenada, Kosovo and Libya were undeclared, even though in most cases Congress did vote approval short of a war declaration — sometimes after the fact. The Korean War was fought under the auspices of the United Nations, the one in Kosovo, by NATO.
With Syria, Israel's safety was a key concern. Dealing a blow to Iranian-backed Syria could mean a retaliatory strike against a key ally staunchly backed by many lawmakers, and some said that any president would need the weight of Congress behind him in such a situation.
"The potential for escalation in this situation is so great that I think it's essential that the president not be out there on his own," Rep. Mac Thornberry, R-Texas, said Saturday in an interview.
But that's a different question than whether to carry out such a strike. Like Cornyn, Thornberry said he wanted to know what the goals would be— and the consequences. In town halls held over the recess, he said, constituents asked him why what happened in Syria should matter to them.
"The president has to convince us," Thornberry said.
What to do about Syria is a politically perilous question for lawmakers, and one that has scrambled loyalties. Still uncomfortably fresh is the memory of the Iraq war and the Bush administration's justification — since disproven — that Saddam Hussein's government possessed weapons of mass destruction.
Liberals who voted in October 2002 against giving Republican President George W. Bush the broad authority to invade Iraq over weapons of mass destruction are echoing Obama's push for punitive strikes against Syria.
Some Republicans who in the past embraced Bush's military doctrine of pre-emptive action — and repeatedly rejected Democratic attempts to end decade-plus conflicts in Iraq and Afghanistan — have rhetorically grabbed 1960s peace signs in warning against the implications of U.S. intervention in the Mideast conflict.
If Obama intended to make the debate less about his leadership and more about the policy, the move to seek authorization didn't work on Rep. Peter King.
King, a New York Republican and a member of the House's intelligence committee, suggested that the president was undermining the authorities of future presidents and seeking a political shield for himself by going through Congress.
"The president doesn't need 535 members of Congress to enforce his own red line," King said.
Associated Press writers Kimberly Dozier, Donna Cassata, Bradley Klapper and Josh Lederman contributed to this report.
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