Ghouta, a suburb of Damascus stubbornly held by rebel fighters, has been a thorn in the side of Bashar Al Assad's embattled forces. On Wednesday sudden death on a large scale came to Ghouta.
Chilling photos and videos suggest that chemical weapons killed hundreds; some estimates put the total over 1,300. If nerve gas was used, this may be the worst such crime anywhere since Iraq's Saddam Hussein gassed the Kurds of Halabja in 1988.
There is, as we have seen over many months now, no controlling the savagery of the Assad regime. But in New York this week his Russian patrons, and the Chinese, have made themselves accomplices, by shamefully blocking a full prompt international inquiry into the deaths.
The regime, of course, denies using chemical weapons, calling the accusations "absurd, illogical and fabricated". Mr Al Assad's defenders argue that he would hardly use gas just as 20 UN inspectors arrived to inspect three sites where such poisons were allegedly used in previous, smaller attacks. This argument almost disproves itself, for the inspectors will not be allowed judge what happened in Ghouta.
They could do so only if the UN asked for access, and the Syrians agreed. But new reports say that in a closed Security Council session at the UN, Russian and Chinese diplomats blocked a proposal from the other permanent members to send the inspectors into Ghouta. A Russian official went so far as to call the attack "a planned provocation on the part of the Syrian opposition".
It is not yet proved that the Assad regime was behind the attack, although few other explanations for the hundreds of unbloodied corpses come to mind. The balance of probabilities points towards the presidential palace. But what might the regime have hoped to achieve by such an attack?
One possible goal could have been to intimidate and inspire fear in the ranks of the rebels and the Syrian people.
Another would be to show the subsequent impotence of the international community - which appears to be exactly what is happening - thereby persuading those who support the rebels that they cannot win, that there will be no international response, that it is time to surrender.
After all, Mr Al Assad might reasonably have calculated, what message would it send if the world watched such a devastating chemical attack, and yet did nothing?