PRESIDENT BASHAR AL ASSAD OF SYRIA IS FIGHTING for the survival of his iron-fisted regime, dominated by the Alawite minority to which his family belongs, amid the staggering political turmoil that has turned the Arab world upside down since the start of the year.
But he has few friends in the Arab world. His only true ally is Iran, and, by all accounts, it is doing all it can to preserve the Damascus regime, a vital element in Tehran's drive to expand its influence across the Middle East.
Tehran has a lot at stake here and its apparent engagement in Syria's increasingly brutal crackdown against dissent reflects the anxiety in Tehran about the possibility of Assad's regime collapsing.
If Tehran loses its air-and-land bridge into Lebanon, through which it funnels missiles and other weapons, Islamic Revolutionary Guard Corps (IRGC) advisers and combat teams to support Hizbullah in its war against Israel, Iran's expansionist objectives in the Levant and westwards into Egypt and North Africa will be seriously curtailed.
"There's a deeply integrated relationship here that involves not only support for terrorism but a whole gamut of activities to ensure Assad's survival," said Michael Singh, a former senior director for Middle East affairs for the US National Security Council during President George W. Bush's administration.
The Americans and their allies have been striving for years to woo Syria away from Iran to isolate the Islamic Republic and break what has been one of the most enduring alliances in the fractious Middle East, where strategic regional partnerships have a habit of collapsing.
Splitting Syria from Iran would end an alliance forged in 1980 by President Assad's father, Hafez, who died in June 2000. Back then, Iran was fighting Iraq's Saddam Hussein, Assad's big rival.
But the alliance did not go down well in the Sunni-dominated Arab world, which saw no good coming from a fundamentalist Shi'ite regime in Tehran.
Nothing much has changed, except perhaps the level of alarm among the Sunni regimes, as US power in the region wanes and Iran's is on the rise.
The Iran-Syria bond has not been broken. It is difficult to determine with any exactitude the extent of the Iranian support Assad's regime is getting. But it should be viewed through the prism of how disastrous the fall of that regime would be for Tehran's strategic ambitions in the region, in particular being able to challenge Israel on its own doorstep.