Every member of the Senate with a glimmer of ambition to run for president - and that's most of them - knows that a vote for war can make or break a political career. The example of Hillary Rodham Clinton, whose vote to authorize the 2003 invasion of Iraq crippled her bid for the Democratic presidential nomination in 2008, is vivid on Capitol Hill.
So while it might be tempting to assume that members of Congress will be thinking solely of the national interest when they vote on President Barack Obama's request for punitive strikes against Syria, there will be old-fashioned politics at work. And the stakes are higher for some than for others.
Obama has the most to lose. Like all his recent predecessors, he doesn't think he needs authorization from Congress to launch missile strikes. But that only underscores that he turned to Congress out of weakness, not strength.
He hasn't been able to build a national consensus for intervention in Syria. He doesn't have the United Nations Security Council, NATO or even the British government at his side. That has left him with two risky options: attack Syria without approval from Congress, or seek authorization and risk an embarrassing rejection.
House Speaker John A. Boehner, R-Ohio, and House Minority Leader Nancy Pelosi, D-Calif., both announced Tuesday they would vote in favor of military action. But most members of the House and Senate haven't declared their positions yet. And many of those who support Obama's request, such as Sen. John McCain, R-Ariz., are using the debate to excoriate the president for what they see as indecision and incompetence.
If Obama loses in both houses, his prestige will suffer a potentially crippling blow; he'll look like the least effective president since Jimmy Carter. If he wins, he'll merely be back where he was a week ago: a reluctant warrior preparing limited military action in the service of a policy he doesn't seem enthusiastic about.
Democrats in Congress are acutely aware of the stakes. Those representing liberal states or districts have to worry about primary challengers to their left. They remember how Sen. Joe Lieberman lost the Connecticut Democratic primary in 2006 because of his support for the Iraq war and had to run as an independent to keep his seat.
Moreover, the party is deeply divided, partly on generational lines. When the Senate Foreign Relations Committee voted 15 to 3 in May to authorize military aid for Syrian rebels, two of the three votes against came from younger liberal Democrats, Chris Murphy of Connecticut and Tom Udall of New Mexico. And in the House, at least 64 Democrats have signed a letter opposing any military strike that "could draw us into an unwise war."
Republicans too know that their votes will have consequences. The party is more deeply divided over foreign policy than at any time in a generation. Hawks like McCain want the United States to do more in Syria, including larger arms shipments to the rebels and use of U.S. air power to impose a no-fly zone. Tea party conservatives like Rand Paul want the U.S. to stay out of the conflict, and polls show that their stance is more popular among Republican voters. Their votes over this month's resolution could turn into a prelude for a battle over GOP foreign policy in the presidential primaries of 2016.
The betting in Washington is that the Senate will pass a resolution authorizing military action, but only after amending it to impose time limits and prohibit any escalation without another debate. The House is harder to predict. The outcome could be something like the 1999 vote on then-President Bill Clinton's airstrikes in Kosovo: a 213-213 tie.
Regardless, the country stands to gain from this debate. We're overdue for a serious conversation on the stakes in Syria. And the vote will serve as a reminder that the constitutional power to declare war still rests with Congress.
For two years, Obama has declared that toppling Syrian President Bashar Assad is an important goal, but he's avoided giving a detailed explanation of a strategy to achieve that end. Now circumstances have forced his hand - and that's a good thing too.
Doyle McManus is a columnist for The Los Angeles Times. Email him at firstname.lastname@example.org.
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