The drumbeat is growing louder and is quickly becoming all that can be heard in Washington. It's a slow, unsteady beat to mark quite the journey for President Obama. He probably guessed he'd be called lots of things, but it's unlikely that "another George W. Bush" was one of them.

We celebrated a dream this past week, but now we're wide awake. Here's a glimpse of some of the top stories your ABC News political team will be tracking in the week ahead:

LONELY AT THE TOP - It's clearer than ever that if and when President Obama chooses to use military force against the Syrian regime, he'll be doing it virtually alone. In seeking to back up his threat against actions that would cross his "red line," he appears to have neither the public, nor Congress, nor the international community (thanks, Great Britain) on his side. He also has a muddled mission that involves retaliation for past actions - a "shot across the bow," as the president himself said this week - more than potentially changing the outcome of a deadly conflict. It's a remarkable situation for a man who rose to prominence warning against go-it-alone international actions. He'll get a chance to see some peers Thursday and Friday in St. Petersburg at the G-20 summit, hosted by Russia's Vladimir Putin. He's got another week before he has to face Congress; congressional leaders in both parties are mostly backing the president on Syria, and have no plans to convene their colleagues earlier than scheduled.

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PLAYING THE FIELD - If history is any guide, how presidential contenders respond and react to events in Syria will linger into 2016 - just ask Hillary Clinton, or John Kerry, or Barack Obama, for that matter. Members of Congress who would be president are hard-pressed to avoid tough stands, even if they don't have to vote on a resolution any time in the near future. Already, Sen. Ted Cruz, R-Texas, and Sen. Rand Paul, R-Ky., have gone quite a bit further than the GOP leadership in suggesting that the president is poised to act outside of the Constitution if he moves in with military force, as ABC News' Shushannah Walshe reports. Sen. Marco Rubio, R-Fla., has focused his critique on Obama's failure to act more quickly and decisively to oust the Assad regime. There's no expectation that Hillary Clinton or Vice President Joe Biden would break with the president in meaningful ways, though any daylight would be significant. And watch the governors: Do any of the 2016ers with state house addresses use Syria to try to hone their national-security credentials? http://abcn.ws/1dti0LA

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BIG DOG, BIG SELL - September is a critical month in publicizing and selling Obamacare, with the Oct. 1 launch of state-based health insurance exchanges. It gets off to a rollicking start next week with an event in Arkansas, with former President Bill Clinton giving a speech on the importance of quality health care to the nation's economy. A policy speech is a policy speech, but recall that President Obama once called Clinton his "secretary of explaining stuff," and you begin to grasp the importance. The White House is helping spread the word about the Clinton speech, and it will be supplemented by a month-long effort involving key principals - the president, First Lady Michelle Obama, Vice President Joe Biden, and Dr. Jill Biden - to spread the word about the new insurance exchanges. The larger goal is to turn around stubborn perceptions about Obamacare, at a time Tea Party Republicans are trying to launch all-out, defund-the-government war over it.

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MAKE IT THERE - There's only one full week of campaigning left in the New York City mayoral primary, which takes place Sept. 10. It's the first citywide election since 1997 without Mayor Michael Bloomberg on the ballot, and Bloomberg's legacy has suddenly taken on outsized importance in the race. Anthony Weiner is barely a factor in the race anymore, but also dropping in the polls is City Council Speaker Christine Quinn. Her ties to Bloomberg are seen as a negative, and that's helping fuel the rise of Bill de Blasio, the city's public advocate. De Blasio's more liberal vision for the city, and his focus on economic inequalities in the Bloomberg era - plus the use of his biracial son in a campaign ad - have upended expectations in the race. Polls suggest de Blasio could even top 40 percent in the primary, the level needed to avoid a run-off. Also vying for a run-off slot, aside from Quinn, is city Comptroller Bill Thompson.

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BACK SO SOON? - Summer isn't really over until Congress is back in session, so in that respect, we get another week. It will be an active week, with Syria rumblings added to the congressional agenda. Headlines on the legislative front have been few and far between, other than stray talk among Tea Partiers about impeaching the president. But the fall promises enormous clashes - an effective deadline on immigration reform, a pair of seemingly intractable budget confrontations, and now a potential constitutional challenge over the use of military force. Suffice it to say that nothing that's happened so far this August have made it more likely that Democrats and Republicans will return to town refreshed and ready to work together, but lawmakers have a week left to change their minds about that.

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