UPDATE: The White House has sent Congress a draft resolution authorizing the use of military force in Syria, Politico reported.

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United States President Barack Obama on Saturday made his most convincing and impassioned argument to date about the need for an American military attack against Syria, as he was consigning it in practice to limbo, if not oblivion. The regime in Damascus heaved a sigh of relief while officials in Jerusalem pulled their hair in exasperation, though both reactions could prove premature.

By asking for authorization from Congress, Obama was transferring the question of the American response to the August 21 chemical carnage in Damascus from backroom strategic and diplomatic deliberations to the polarized, rough-and-tumble arena of open-air politics. He decided to share the onus of responsibility for dealing with what he described as the Syrian “assault on human dignity” with the representatives and senators who have been incessantly sniping at him without paying a political price.

I dare you, Obama is challenging his critics, to smear yourselves and America with the stain of isolationism and timidity.

Obama decided on this course when he found himself – through much fault of his own - with none of the prerequisites of international backing, public support or constitutional legitimacy that he had once chastised George W. Bush for ignoring. “The president does not have the power under the constitution to unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat to the nation,” Obama said in 2007, as he waded into the complex and historic tug of war between the president and Congress over the power to wage wars.

Obama is obviously taking a risk that he will suffer a political defeat that will be even more humiliating than the one inflicted on David Cameron by the British House of Commons. But he could also be rewarded with a victory that would give him much more public and political backing – and thus greater military and diplomatic freedom of action – than he seems to have now.

Obama may have hemmed and hawed his way to this juncture – especially when compared to the rhetorical brilliance and conviction shown on Friday by Secretary of State John Kerry in his presentation of the damning evidence against the Assad regime – but political campaigns, contrary to military incursions, are the president’s forte. He may be reluctant and hesitant when it comes to Syrian generals, but he is spoiling for a fight and full of surprises when it comes to his political rivals.

The stage has thus been set for a riveting political and public debate that will pit the two parties against each other and each within itself. It will mix and match the political with the constitutional, the strategic and the expedient, the loftily ideological and the blatantly personal. Instead of the war epic that everyone expected, a political thriller of high drama a la "House of Cards" will be played out before the American audience.

Democrats will be torn between their liberal idealism and their loyalty to the president, Republicans between their hawkish patriotism and their burning wish to cripple Obama, regardless of cost. If polarization prevails, the Democrat-controlled Senate will consent, the Republican-dominated House will oppose, Obama will have no mandate to act but he will be given a convenient scapegoat to blame. If lawmakers are allowed to vote their conscience, the campaign will see strange bedfellows and peculiar coalitions as leftist pacifists team up with Tea Party isolationists against moderate centrists and conservatives on both sides of the aisle.

In this showdown, Israel and the lobby that supports it may find themselves suddenly embroiled. Both have been careful to steer clear of taking sides and to appear neutral for fear of fueling Iraq War, Walt and Mearsheimer-style attacks that Israel and its doers in Washington were pushing America to go to war. But it is surely no coincidence that both Obama and Kerry have made a point of reiterating time and time again that in advocating a strong response to Syria, the U.S. is looking out for Israel and its interests, by preventing the proliferation of chemical weapons and by sending a strong signal to Iran about its nuclear plans.

Supporters of Israel will likely be told that at this critical juncture, neutrality is a luxury that neither the lobby nor the Administration can afford. Time to put up or shut up, get off the fence and spend some of the precious political capital that Israel supporters have amassed in order to fight in the Washington trenches for something that most Israelis contend is crucial to their national interests.

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Open gallery view An anti-Assad protester holds a picture of the Syrian president during a march in demand for US attacks on Syria in front of the White House in Washington, DC on August 31, 2013. Credit: AFP