For the second time this year, the Arab League – usually regarded as one of the world's most ineffectual and divided organisations – has shown a surprising sense of unity and purpose with regard to one of its own members' behaviour. 

In March it called for a no-fly zone over Libya and now it has decided to suspend Syria's membership.

The suspension vote on Saturday was opposed only by  Lebanon, Yemen and Syria itself, with Iraq abstaining – giving a solid majority of 18 votes in favour. This was the first time such action had been taken since 1979, when Egypt was suspended for making peace with Israel.

Syria undoubtedly has a point when it says the decision is in breach of the Arab League's charter. The charter, promulgated in 1945, is obsessed with protecting members' national sovereignty and article 8 spells it out very clearly:

"Each member-state shall respect the systems of government established in the other member-states and regard them as exclusive concerns of those states. Each shall pledge to abstain from any action calculated to change established systems of government."

On that basis, it's difficult to see how the league can justify its action legally, except by force of circumstance: that it's better for Arab states, collectively, to try to put their house in order than to stand by and leave it to outsiders.

Having reached this stage, however, Assad's protests about sovereignty ring somewhat hollow. He undermined them himself earlier – by engaging with the league over its "peace plan" and agreeing to its provisions (which he has since made no serious effort to implement) – so he can scarcely object now if they punish him for breaking his word.

There is also a certain irony in seeing the league, which is still at root a dictators' club, attacking one of its own kind. Many have pointed out on Twitter that the league still seems unwilling to tackle other murderous regimes in its midst, such as those of Yemen, Bahrain and Sudan. That is not an argument for inaction over Syria but it does reflect a double standard. If we ask "Why Syria?", a large part of the answer is that Sunni rulers, especially in the Gulf, are fearful of Iran – and Syria is Iran's principal Arab ally.

The big question, of course, is what impact the league's decision will have on the situation.

First, it makes a mockery of Assad's claims that the uprising is some kind of American/Zionist plot against his regime. He may well try to make out that the Arab League has been nobbled by Americans and Zionists too but, even for the Assad loyalists, that would surely be stretching credulity too far.

Secondly, in the light of such a clear Arab consensus, Russia and China may find it more difficult to continue resisting tougher sanctions against Syria in the UN security council.

Finally, in the wake of Syria's suspension, the Arab League is talking of developing its incipient ties with the opposition and trying to help unify it. If it does go down that road (and we can't be certain at present that it will), the anti-Assad forces inside the country would receive a huge boost – psychologically at least and perhaps in practical ways too.

Beyond that, though, and perhaps most important of all, the league's decision implies that Arab states no longer expect Assad to survive. Theoretically, he could be rehabilitated in the unlikely event that he complies with the "peace plan" but, for all practical purposes, 18 of the league's 22 members have now burnt their boats and are beginning to prepare for the post-Assad era.

That doesn't mean the regime's fall is imminent but, if we couple all this with the growing economic pressures (here and here), its position is looking more precarious than at any time since the uprising began.

Posted by Brian Whitaker, 13 November 2011