The big question for Syrians, as nationwide unrest increasingly focuses not just on the Ba'athist regime but on its floundering leader, is whether President Bashar al-Assad will be forced from office like his Egyptian and Tunisian counterparts. But for western and regional governments, the key question is a more self-interested one: is Assad's fall desirable? The unspoken answer is mostly "no". The resulting policy may be termed the Syrian sell-out.

It's true the US and its European allies, Britain among them, have expressed serious concerns about the violence that is believed to have left more than 200 people dead. The Foreign Office has repeatedly urged Assad to end the forcible suppression of peaceful protests and embrace democratic reforms. The Obama administration has adopted a similar exhortatory stance.

But unlike Egypt, where the US and Britain, after some dithering definitively took sides in urging Hosni Mubarak to stand down, and unlike Libya, where they have intervened militarily to assist the opposition, Washington and London have taken no concrete steps to bolster the Syrian demonstrators or punish the regime. No sanctions, no asset freezes, no embargos, no aid cuts, no diplomatic disengagement, and certainly no no-fly zone.

One reason given for western passivity is that the US, in particular, has comparatively little leverage. Syria is already the subject of American sanctions and diplomatic relations are tenuous. More to the point, however, the US and Britain worry that Assad's fall, and the prolonged instability, even civil war, that they assume would ensue, would undermine Israel-Palestine peace efforts (such as they are), upset delicate political balances in Lebanon and Iraq, and provide an opening for al-Qaida-style extremists.

Regional countries also favour the Syrian status quo for self-interested reasons. Turkey believes chaos in Syria could revive separatist agitation among the country's Kurdish minority, with knock-on impact in south-east Turkey. Israel worries a new Syrian government might push more aggressively for the return of the Israeli-occupied Golan Heights. Saudi Arabia is opposed, in principle, to anything that smacks of democracy.

Nor is Europe exactly cheerleading change, despite the obvious contradiction in its attitude towards Muammar Gaddafi. The fact that the EU is Syria's largest trading partner, and Europe buys Syrian oil, may have a bearing.

Naturally, this repellent consensus is not publicised or bruited about. In theory, all these governments support reform. But in private they mostly subscribe to the view expressed by New York Times columnist Thomas Friedman that the Arab world upheavals now more closely resemble Yugoslavia in the early 1990s than eastern Europe after the Soviet Union collapsed.

In other words, in largely unhomogenous Arab countries, with the exception of Egypt, Tunisia, and Morocco, civil war is the more probable outcome of spiralling unrest than is peaceful, democratic evolution – and multiethnic, multiconfessional, institutionally fragile Syria is a prime risk.

Not everybody supports the Syrian sell-out. Some influential voices have been raised in protest. David Schenker, Levant director at the Pentagon in the Bush administration, argued in New Republic that fear of what might follow should not deter the US from pushing for Assad's departure – since nothing could be worse than him.

The fondly nurtured belief that, unlike his father, Assad is a reformer at heart had been thoroughly discredited, Schenker said. "[Assad] has spent his first decade in power recklessly dedicated to undermining stability – and US interests – in the Middle East … As the brave Syrian people do the hard work and pay a high price to rid themselves of a corrupt, capricious and brutal dictator, America should not be throwing him a lifeline."

Boston Globe columnist Jeff Jacoby urged the White House to lend muscular support to the pro-democracy movement. "[Assad's] reign has nevertheless been a horror show of repression, torture, assassination, disappearances and the near-total denial of civil and political liberties," he said. A golden opportunity to dump him should not be missed.

Elliott Abrams, Middle East director of the US national security council under Bush, said Assad's departure was desirable because, if for no other reason, it would be a serious blow to Iran, which is said to use Syrian territory and ports to transport arms to Hezbollah in Lebanon and Hamas in Gaza.

"This regime has seen us as an enemy, and I just don't understand the notion that Assad is a reformer and that this regime can be reformed. It cannot be," Abrams told the Washington Post. "What bothers me most is that this administration… is failing to see the huge benefit we would achieve should [the regime] fall."

Some Whitehall officials share these sentiments, describing Syria under Assad as a seriously unhelpful regional player, a supporter of terrorism, and a Middle East "aircraft carrier for Iran". Britain and the US should "take a risk on revolution".