as he decided to pull back from certain strikes on Syria to going to the US Congress for a vote when it reconvenes today.
Obama doesn't need the vote, and the small possibility of losing as David Cameron did in the British Parliament, makes this one of the biggest gambles a US president has taken on policy-making.
"Here's my question for every member of Congress and every member of the global community," the US president challenged, "What message will we send if a dictator can gas hundreds of children to death in plain sight and pay no price?"
The open-ended question not as much a throwing of the gauntlet, as it is a sign Obama hoped that his colleagues in Congress could make the call on what to do instead. But unfortunately, Obama has already painted himself into a corner in a room full of smoke with no signs of a safe exit door.
Let's take a look at the US's case for action on Syria after the reported chemical attack of ' 21, and analyse why Obama may actually want to be second-guessed. To begin with, is the "high confidence" touted by US secretary of state Kerry that Syrian President Bashar al-Assad had carried out the attacks, based on its intelligence report, highlights of which the State department made available.
According to the report, satellite movements, artillery reports, and the images on video all lead to the conclusion that the Syrian regime had targeted the Damascus suburb of Ghouta with chemical weapons.
Yet the report itself says that the chemical-laden rockets had been fired from "regime controlled territory", not identifying the Assad Army brigade that may have been responsible for "the deaths of 1,429 people, among them 426 children."
The French intelligence reports based casualty figures on "methodical, technical analysis of 47 original video tapes," putting the figure at 281, saying non-governmental assessments were higher.
The British intelligence report, that failed to help PM Cameron win his Parliament vote, put fatalities at 350, conceding only "some intelligence to suggest regime culpability in this attack".
The differing casualty figures are puzzling, and it is extremely clear that the strongest case they all make to blame Assad is that "no one else had the capability to do it". Hardly the stuff of a water-tight case.
The US administration can also not use public pressure as reason to act in contravention of the UN Security Council's mandate. In a poll of three European countries ù Britain, France and Germany conducted by Comres for CNN, only 23% of participants backed strikes on Syria, even less than the 26% that voted to "do nothing" at all as an option.
In the US, an ABC/Washington Post poll found 59% opposed the US's strike plan, while only 36% supported it. Even the Arab League countries, that the US often cites, voted that action against Syria must be UN-mandated.
If Assad and his forces are indeed guilty of what they are accused of, a limited set of punitive strikes would hardly deter them. The option of not acting, regardless of what Congress says, seems remote. In an interview to CNN last week US House Intel Chairman Mike Rogers put it starkly.
"When the president called for a red-line [over the use of chemical weapons], the full credibility of the US was put on the line. "
As Obama prepares for that no doubt compelling speech he will make at the US Congress soon on striking Syria, he must remember the pacifist sentiments he expressed in his acceptance speech of the Nobel peace prize in 2009.
Suhasini Haidar is foreign affairs editor, CNN-IBN
The views expressed by the author are personal