If there are no limits in Syria, there will be none elsewhere Friends of the Assads deliver, while the so-called Friends of Syria are paper tigers Last week's chemical weapons attack on the eastern suburbs of Damascus is an atrocity comparable to the Saddam Hussein regime's gassing of Halabja in 1988, and the war Bashar al-Assad has waged on his own people surpasses even the crimes of Slobodan Milosevic in the wars of the Yugoslav succession. No, we do not know for sure it was the government that carried out the attack, which killed well over 1,000 people, many of them children. Logic suggests it would be insane for the regime to fire chemical shells across its beleaguered capital just as United Nations chemical weapons inspectors arrived in Damascus. But whose logic is operating here? By dismissing rebel charges that loyalist forces committed this war crime as "illogical," the Assads merely repeat the standard cui bono argument they have wheeled out after almost every atrocity and assassination they have perpetrated over the past four decades: how could it be them if they are the ones who would obviously be blamed? And yet it so often was them. Syrians have a sardonic proverb that sums it up: "They kill you and then march at the head of your funeral cortege." If it was not them, they should already have frogmarched the UN inspectors into the eastern Ghouta suburbs where the shells fell. Even Russia, the Assads" steadfast ally which at first dismissed the attack as a rebel provocation, is now urging Damascus to cooperate with the UN - which Syria now claims it is willing to do. Circumstantial evidence also suggests the regime is responsible for this barbarity. It is reasonably certain it has already used chemical weapons, although not on this scale. Eyewitnesses report the rockets were fired from government territory. It is the Syrian army that has the capability to mount such a concentrated attack. And the regime has in any case forfeited the right to presumption of innocence by virtue of its daily savagery over more than two years. If they are not guilty, the inspectors can prove they have nothing to hide. Even so, many Syria-watchers are still puzzled as to why the Assads would do this. After months on the military ropes, they are on a roll. Since the fall of Qusair in June, and the recapture of the Homs Gap in an offensive led by Hizbollah, the Iran-allied, Lebanese Shia paramilitaries, Damascus has gone on the offensive. The overt commitment of Iran and Hizbollah, along with Russia's diplomatic shield at the UN Security Council, shows that the Friends of the Assads deliver, while the so-called Friends of Syria, with their mostly hollow pledges to arm the rebels, are paper tigers. But while the fall of Qusair has flattened the few remaining barriers to this conflict turning into an out-and-out sectarian fight between Sunni and Shia, grafting a schism within Islam and the regional contest between Iran and Saudi Arabia onto what began as another Arab struggle against tyranny, nothing strategic has changed. The regime still cannot recapture vast swathes of the north, east, and south east. Eastern Ghouta itself presented a stubborn rebel threat to the capital. At the same time, Bashar al-Assad has enjoyed virtual impunity, as his international opponents, in particular the US, have huffed and puffed and blown down their own credibility. Mr Assad had already got away with tentative use of chemical weapons, for all President Barack Obama's "red line" warnings. He will have studied Washington's feeble response as the army restores the old order in Egypt. His is a regime, remember, that set up a recruiting station for jihadis outside the US embassy in Damascus immediately after the invasion of Iraq; he is still there, while the Americans and British have departed an Iraq now pushed by Iran into backing him. Why not strike terror into the heart of all in Syria who oppose him, and show them they are alone and helpless against violence that need know no limits? The Assads have shown they are ready to destroy Syria and decimate its people to reimpose their right to rule. After last week - described by Mr Obama as "a big event of grave concern" - the world will be watching to see if it is indeed true there are no limits. Because, if there are none for Mr Assad, then there will be none for tyrants elsewhere who learn this lesson of international impunity and emulate his depravity.