For politicians eyeing higher office, congressional votes to authorize military action can have lasting consequences.
Just ask Hillary Clinton, whose 2002 vote to use force in Iraq gave Barack Obama his opening to defeat her in the 2008 Democratic presidential primary.
Clinton - widely considered the top contender for the 2016 Democratic nomination - weighed on Tuesday evening after days of silence following Obama's call for congressional approval for military intervention in Syria.
"Secretary Clinton supports the President's effort to enlist the Congress in pursuing a strong and targeted response to the Assad regime's horrific use of chemical weapons," a senior aide to Clinton told NBC News.
Now, the spotlight falls to Congress, as the Obama administration makes its case for a strike this week on Capitol Hill.
All eyes are on the handful of senators who might run for president three years from now and beyond, including Sens. Ted Cruz, R-Texas, Rand Paul, R-Ky., and Marco Rubio, R-Fla.
But just as importantly, it shifts the focus away from White House hopefuls who don't currently serve in Congress or in the Obama administration, such as New Jersey Gov. Chris Christie, Wisconsin Gov. Scott Walker and Clinton.
After all, these politicians don't have to cast a vote that raises a host of questions: Should the U.S. respond to a country's use of chemical weapons on its own people? Or does it turn the other way? Is using force in the United States' national interest? Or does it open a Pandora's Box in the troublesome Middle East? And is it time for a war-weary nation to stop being the world's policeman? Or does inaction ultimately empower Iran and alienate a U.S. ally like Israel.
Those are all tricky questions that the current Congress -- and the 2016 aspirants who serve in it -- must consider.
Paul, Cruz and Rubio weigh in
On NBC's "Meet the Press" on Sunday, Paul said he opposed using force in Syria.
“I think it's a mistake to get involved in the Syrian civil war," he said. "I would ask [Secretary of State] John Kerry, ‘Do you think that it's less likely or more likely that chemical weapons will be used again if we bomb Assad?’ I'll ask him if it's more likely or less likely that we'll have more refugees in Jordan or that Israel might suffer attack. I think all of the bad things that you could imagine are all more likely if we get involved in the Syrian civil war."
During questioning at Tuesday’s Senate Foreign Relations Committee hearing, Paul said it was still unclear whether a strike would increase the likelihood of more violence in the region.
“I think there’s reasonable argument that the world may be less stable because of [a strike] and that it may not deter any chemical weapons attack,” he said. “So what I want to ask is, how are we to know?”
Cruz released a statement on Saturday hinting that he's a "no" too, although he said he welcomed the debate and implored President Obama to make his case to the country.
"I remain concerned that the mission proposed by the president is not in furtherance the vital national security interests of the United States. To date I have heard a great deal from the administration about punishing Bashir al-Assad for violating an 'international norm' through the use of chemical weapons, and that this is why we must act against him," he said. "Abstract notions about international norms should never displace U.S. sovereignty to act, or refuse to act, for our national security."
For his part, Rubio was non-committal in his statement.
“I agree with the decision to seek congressional approval before taking military action in Syria. And I believe Congress should return to Washington immediately and begin to debate this issue," he said. “The United States should only engage militarily when it is pursuing a clear and attainable national security goal. Military action taken simply to send a message or save face does not meet that standard.”
These potential Republican presidential candidates must navigate two political cross-currents -- a GOP base that reflexively opposes President Obama but one that also reflexively supports Israel.
“Right now, the easy Republican vote looks like the vote against Obama,” neoconservative lobbyist and writer Michael Goldfarb told the New York Times. “Ten days from now, a vote against Obama could look like a vote for Assad, especially if Republicans succeed in blocking U.S. action, and Assad goes on to prevail, having used chemical weapons, with Iran at his side.”
NBC's Andrea Mitchell contributed to this report.