The United States says it can't afford to turn a blind eye to incontrovertible evidence of horrific gassing of children and civilians by Syria's brutal regime. So despite war-weariness at home and skittish allies abroad, President Barack Obama is on the verge of ordering a punitive military strike.
"I've not made any final decisions," Mr. Obama said Friday, adding that, at most, he was mulling a "limited, narrow act," widely expected to be a short, sharp attack. Seeking to reassure Americans leery of yet another war against a Muslim nation, the President hedged on timing and promised ongoing consultations with allies and the American people. He was unequivocal that there would be "no boots on the ground," meaning no invasion of Syria involving U.S. troops and no war for regime change or to oust President Bashar al-Assad.
Mr. Obama is in a bind. His intelligence agencies confirm there is hard evidence of "brutal and flagrant" chemical weapon attacks by Syrian government forces against rebel-held neighbourhoods in Damascus – the so-called red line the President painted more than a year ago. On Friday, the White House released a four-page unclassified summary of evidence, grimly detailing Mr. al-Assad's war crime – deemed so because chemical weapons have been outlawed since the First World War.
"The United States government now knows that at least 1,429 Syrians were killed in this attack, including at least 426 children," said Secretary of State John Kerry. "This is the indiscriminate, inconceivable horror of chemical weapons. This is what Assad did to his own people."
The latest attack was the worst and most blatant, but hardly the first use of poison gas in the bloody sectarian strife that has killed more than 100,000 Syrians over more than two years.
But as Mr. Kerry made clear in his tough-talking speech Friday, what is now at stake is far larger than establishing mass murder by the despotic Assad regime using outlawed weapons.
Mr. Obama's response will determine the President's personal credibility, confirm or diminish the status of the United States as the world's sole remaining superpower and – most of all – set the bar in deterring others from using weapons of mass destruction.
It may also roil the Arab street and could set off a wider regional conflict.
That risk, Mr. Kerry made clear, must be taken.
"If we choose to live in the world where a thug and a murderer like Bashar al-Assad can gas thousands of his own people with impunity, even after the United States and our allies said, 'No,' and then the world does nothing," it will embolden others, Mr. Kerry warned.
"It is about Hezbollah and North Korea and every other terrorist group or dictator that might ever again contemplate the use of weapons of mass destruction. Will they remember that the Assad regime was stopped from those weapons' current or future use? Or will they remember that the world stood aside and created impunity?"
For Mr. Obama, whose original bid for the presidency rested squarely on denouncing the Iraq War and scorning his predecessor for launching an attack based on an intelligence assessment that flatly – but wrongly – asserted that President Saddam Hussein had weapons of mass destruction, the prospect of waging even a short, limited conflict with few allies, no UN Security Council resolution and strong opposition at home is a huge political gambit.
So Mr. Kerry was guaranteeing limits well in advance. He admitted that the ghosts of decision-making about Iraq haunted the Oval Office. "Our intelligence community has carefully reviewed and re-reviewed information regarding this [Syrian poison gas] attack," adding the Obama administration was "more than mindful of the Iraq experience. We will not repeat that moment."
Distancing Mr. Obama from previous presidential war-making moments seems pivotal.
"Whatever decision he makes in Syria, it will bear no resemblance to Afghanistan, Iraq or even Libya," said Mr. Kerry, adding any punitive military strike against the Assad regime "will not involve any boots on the ground, it will not be open-ended and it will not assume responsibility for a civil war that is already well under way."
With staunch ally Britain already opting out of any attack on Syria, and Russia, a veto-wielding UN Security Council member, making it crystal clear that Mr. Obama won't have the cover of an international war-fighting resolution as he did in Libya, the President faces etching his interventionist legacy in history almost alone.
"President Obama will ensure that the United States of America makes our own decisions on our own timelines, based on our values and our interests," Mr. Kerry said. "We know that after a decade of conflict, the American people are tired of war ... but fatigue does not absolve us of our responsibility."
Mr. Obama, who vowed more than a year ago that the use of chemical weapons by the Assad regime was the uncrossable red line, is at a tipping point in his presidency. Already under fire for the massive, secret and unprecedented digital tracking of Americans as well as foreigners, and with his aggressive and deadly drone strikes continuing to kill around the globe, Mr. Obama now faces the prospect of ordering military attacks almost devoid of allies or international legitimacy.
Only France – "our oldest ally," as Mr. Kerry wistfully said – has announced a willingness to join the United States in any military attack on Syria.
The Canadian government, like Britain's, has refused to join any U.S.-led military action. "Canada is not contemplating its own military mission, but we do support our allies," Prime Minister Stephen Harper's spokesman Andrew MacDougall said after Mr. Kerry's speech. There was no indication what form that support would take.
Some still hope Mr. Obama can step back from the brink of war, no matter how limited, without losing face or tarnishing America's credibility.
"Diplomacy should be given a chance and peace given a chance," said UN Secretary-General Ban Ki-moon.
After 900 days of steadily mounting bloodshed, and despite repeated calls by Mr. Obama and others that he should step down, the Syrian President has shown no signs of heeding diplomacy.