The more McCain acts like he wants a bigger war, the easier the media will find it to explain that it was all the fault of the Republicans.
That's the argument that Bill Kristol makes and it's credible enough as far as that goes.
A Yes vote is in fact the easy vote. It's actually close to risk-free. After all, it's President Obama who is seeking the authorization to use force and who will order and preside over the use of force. It's fundamentally his policy. Lots of Democrats voted in 2002 to authorize the Iraq war. When that war ran into trouble, it was President Bush and Republicans who paid the price. If the Syria effort goes badly, the public will blame President Obama, who dithered for two years, and who seems inclined to a halfhearted execution of any military campaign. If it goes well, Republicans can take credit for pushing him to act decisively, and for casting a tough vote supporting him when he asked for authorization to act. . .
Sure that's politics as usual. But there are a few things worth remembering...
When the Democratic Party turned on the war, it also turned on some of its more prominent senators who had supported it. The left seized the opportunity to carry out a purge of the party that twisted it to the left resulting in the Obama Reign of Error.
A Republican version of this might well be a successful resurgence of the Tea Party. All that assumes a prolonged and disastrous Syrian War with American casualties. But I still wouldn't push expediency that far even if gains like these were assured.
But I think the suspect assumption is that politics as usual will operate.
Obama has yet to get the blame for anything in a way that sticks. He could invade Iraq a second time and the media would spend every hour of airtime insisting that it was Bush's fault.
Senator McCain has made their work easy for them by repeatedly denouncing Obama for not going big enough. All those criticisms make it easy to blame the war on Republicans.
The more McCain acts like he wants a bigger war, the easier the media will find it to explain that it was all the fault of the Republicans. And a surprising chunk of the public will buy it.
Bush couldn't have gotten away with blaming Hillary Clinton, but Obama could easily get away with blaming McCain.