President Bashar Al-Assad took an enormous gamble if his forces were behind the chemical weapons attack that killed dozens in northern Syria: committing an overt war crime just as the Trump administration and most Western leaders had made clear they are no longer seeking his immediate removal.
Although Assad can count on the backing of his top allies, Russia and Iran, the attack has revived international outrage at a time when US President Donald Trump is still formulating his policy on Syria.
So why do it? Especially when Syrian government troops have the upper hand in the 6-year-old civil war? There is a military rationale, as well as a political one, analysts say.
Politically, Assad may have been emboldened to act to crush his opponents, thinking he could do so with impunity after recent statements from Washington, along with Trump's inclination to align with Russia.
On a visit to Turkey last week, Secretary of State Rex Tillerson said Assad's future was up to the Syrian people to decide, while Nikki Haley, the American ambassador to the UN, said the US isn't ruling out cooperation with Assad to defeat the IS.
Militarily, Tuesday's attack took place in an area of Idlib province where rebels recently launched a heavy offensive against government troops. The assault brought insurgents to within miles of the key, government-held city of Hama. Khan Sheikhoun, the town targeted by Tuesday's attack, is right up the road from Hama, and although Syrian forces have since launched a counter-offensive and regained some ground, there is a clear government incentive to rid the area of insurgents.
Still, a chemical weapons attack of this magnitude carries significant risk.
The images of lifeless children and others gasping for breath were reminiscent of the 2013 attack near Damascus that killed hundreds of civilians, and triggered a blitz of denunciations by world leaders and organisations, who urged the US to commit to a Syria solution.
Trump's condemnation of Tuesday's attack has been surprisingly strong, even if he did not give any clear indication about how the US might respond.
On Wednesday, Trump denounced the attack as an "affront to humanity" and blamed Assad, saying it "cannot be tolerated." At the UN, Haley threatened unilateral US action if the world body failed to act.
Part of the equation, for any perpetrator, is the difficulty of proving anything in the aftermath of such attacks, largely due to the lack of immediate access. And, in the complex terrain of opposition-held northern Syria, which is closed off to investigators and journalists, various scenarios cannot be completely discounted.
Some analysts suggested Assad may be signalling he wants quicker action to end the war on his own terms.