Russia isn't wrong to say that this week's apparent chemical weapons attack near Damascus in Syria could be a provocation, inflicted by rebels against their own to trigger international intervention. The timing of the attack was certainly odd, just as United Nations chemical weapons inspectors arrived in town. False flag attacks do happen in conflicts.

Relative to Russia's role in watering down language at the United Nations Security Council's emergency session, though, who cares?

Russia and China blocked the use of wording that would have applied the authority of the Security Council to the task of investigating the attack. A draft by the U.S. and its allies would have specified -- imagine this -- exactly which alleged chemical attack was under discussion. Even that was too much for Russia's diplomats. The gutted draft also would have called for the UN to "urgently take the steps necessary for today's attack to be investigated by the UN mission." And it would have demanded that President Bashar al-Assad's regime "allow safe, full and unfettered access to the UN mission" as well as "comply with all requests for evidence and information."

So once the Russian and Chinese diplomats had wielded their whiteout, what did we get? The world's most powerful nations pronounced a "general sense there must be clarity on what happened," and welcomed UN Secretary General Ban Ki-Moon's plans to investigate.

This leaves the question of negotiating the details of any investigation up to UN officials and Assad, alone. If Assad blocks the inspectors from the site, as he did for months on end after previous allegations of chemical weapons use, then so be it. The Security Council is not involved. Assad will certainly understand the message: Even the use of chemical weapons on a scale not seen since Saddam Hussein killed up to 5,000 ethnic Kurds at Halabja in 1988, will not draw a meaningful international response. President Vladimir Putin still has his back.

If the Russians really believe this was a provocation, why the reluctance to force its investigation? One answer is an allergic reaction to allowing the U.S. any kind of legitimization from the Security Council when it comes to Syria, because of the expansive way in which NATO allies interpreted the 2011 resolution to protect civilians in Libya. Russia let that one slide and then regretted it, bitterly. Plus there are simple, cynical, power politics at play: Russia doesn't want Assad to lose and is willing ignore his use of (Russian-designed) chemical weapons as he fights.

It's hard for the U.S. to take the high ground. In 1988, the Reagan administration lobbied fiercely to defeat the Prevention of Genocide Bill in Congress, which would have imposed sanctions on Saddam's Iraq in response to the Halabja killings -- after all, Iraq was fighting Iran at the time, and Iran was the enemy. The U.S. administration said both sides were using chemical weapons, attempting to blur the allocation of guilt and give Saddam a pass. It also watered down UN Security Council condemnation of the atrocity, to just as pernicious effect as Russia's intervention on Syria, on Aug. 21.

So stop the presses: Great powers can be cynical. But I think also short-sighted. What did the U.S. get from protecting Saddam from the consequences of his chemical weapons' use at Halabja? Two years later it was invading Iraq at enormous expense, because Saddam had annexed U.S. ally Kuwait. Presumably Saddam had concluded the U.S. wouldn't respond. The U.S. paid the price again in a second Gulf War, and continues to pay. Plus it must carry the shame of protecting the culprit in a heinous war crime -- history tends to lay such things bare. It would have been better for the U.S. then, and Russia now, to draw bright lines about what the international community will not accept. The use of chemical weapons against civilians should surely be one of them.

(Marc Champion is a Bloomberg View editorial board member. Follow him on Twitter.)