Assad must choose: alienate his allies or lose control of Syria

Bashar Al Assad is entering a crucial phase in his response to the revolt in Syria, with twin crises showing no signs of abating.

The monitors have arrived and President Bashar Al Assad's forces are busy giving them rubble to monitor, with shelling in several districts of Homs continuing into yesterday morning.

The ceasefire and entry of the monitors, brokered by former UN secretary general Kofi Annan, have begun. Both sides have violated the ceasefire, but as of last night it was holding in a broad sense despite the reported shelling of some cities.

Mr Al Assad is entering a crucial phase in his response to the revolt, with twin crises showing no signs of abating. The next few weeks will prove crucial to his survival: the internal uprising is evolving into a grinding struggle, while external diplomatic pressure continues. Mr Al Assad will need to repeatedly make the right political decisions if his regime is to survive.

After the initial uprising was seemingly suppressed, Mr Al Assad's problem is now that the attempt to unseat him has adapted for a long struggle. The peaceful protesters, who still make up the bulk of the uprising, have for the time being been sidelined by the armed revolt. That revolt continues - on Sunday, armed men attacked a police station in Homs and there were reports yesterday of more defections to the Free Syrian Army - but its tactics have changed in response to the regime's brutality.

In militant Islamist circles in the 1970s and 1980s, one proposed strategy was to take over a single city, and then use that population centre as a launching pad for an Islamist uprising. In 1982, when Hafez Al Assad crushed the uprising in Hama, that idea was discredited, and Syria's Islamists were arrested, forced underground or fled into exile.

(Some Islamist thinkers, including militants, afterwards concluded that the best way to wage "holy war" would be to dominate an entire state from which to launch attacks - this thinking brought many like-minded fighters to Afghanistan in the 1980s.)

Today's Syrian protesters, and the armed contingent of the opposition, also seem to have concluded that they cannot hold a city against the army after they were forced to flee the Baba Amr district of Homs. Instead, they appear to be preparing for a long guerrilla campaign of flash protests, popping up and vanishing before the regime can react, with the armed contingent staging brief attacks.

Mr Al Assad's army is badly equipped to handle that kind of threat. With the exception of the elite Republican Guard, the army is poorly equipped, and lacks training and motivation. The longer the uprising continues, the more army units will defect - while it is unlikely that a tipping point will be reached any time soon, the longer the insurgency continues, the more difficult it will become for Assad troops, who will be ordered to search, detain and shoot their own people. The law of diminishing returns applies - the longer the protest movement lasts, the more repression the regime will need to wield with less returns.

At the same time, other countries are closely scrutinising Mr Al Assad's reaction. Some of his regional neighbours have put their cards clearly on the table. Turkey and Qatar, in particular, want the Assad regime to fall and continue to apply serious pressure. Iran and Israel, for different reasons, fear the end of Assad rule: Iran would lose its most valuable Arab ally; Israel fears a democratic government that would probably take a tougher line on the occupation of Syrian and Palestinian land.

The outside world has been more reluctant, but it is also losing patience. Even Russia and China's, Syria's two supporters on the UN Security Council, were persuaded to back the latest UN resolution on ceasefire monitors. If the Annan peace plan falters, Mr Al Assad may lose the support of those two heavyweights.

These are the horns of Mr Al Assad's dilemma: the more he fights internal dissent, the more he faces external criticism. If, in order to placate the outside world, he calls off his troops, he faces a renewed uprising. His survival requires a delicate political balance.

A glimpse of this came last week when Syrian troops opened fire across the Turkish border, killing two people in a refugee camp. Turkey threatened serious consequences, but in the end did not react. If the Annan plan fails, Ankara might take another such provocation as a justification of greater involvement in the uprising, potentially sparking a wider conflagration or external intervention.

For now, Mr Al Assad is trying to face both ways: using heavy force to crush the protesters, while pretending to abide by the diplomatic niceties by agreeing to the Annan plan. But he cannot continue. Despite regime declarations that the conflict is over, it is not. A long hot summer of guerrilla tactics beckons, with a watching world. In the coming weeks, Mr Al Assad will face the repeated decision of whom to cross, his citizens or his neighbours. His survival depends on those decisions.

On Twitter: @FaisalAlYafai