Instead, he answered protests with guns. Demonstrations multiplied across the country and turned violent. Into the resulting maelstrom stepped Assad's allies, Russia and Iran, to protect their investment in his continued rule. The US dithered, half-heartedly supporting some rebel groups but mostly staying away.

Iran-backed fighters from Lebanon, Iraq, and Yemen backed the Syrian army. Well-armed Syrian Kurds saw an opportunity to win greater autonomy by weakening Assad. Fundamentalist extremists of various tribes joined the fight. Turkey sent soldiers, and Saudi Arabia provided cash and weapons to destabilize Assad. Western powers intervened to try to contain the carnage.

Assad's army — with backing from its friends — bombed hospitals, tortured prisoners, and used chemical weapons against civilians. The Obama administration warned these crimes crossed a "red line" but did virtually nothing to enforce it. In total, years of shooting, shelling, and bombing has killed hundreds of thousands of Syrians, about 22,000 of them children.

The war is now over, though the Syrian army hasn't recaptured all its northern provinces. Assad has won because those with the deadliest weapons were willing to commit atrocities to survive, and because outsiders did far too little to stop them.

The cost

Today, more than half the 22 million people living in Syria in 2011 have been forced from their homes. Six million are now in other countries. Turkey, Lebanon, and Jordan host more than 90 percent of these refugees.

Of those who weren't able to escape, thousands have been murdered inside Syrian prisons, and tens of thousands more prisoners remain missing, according to a report from the UN Human Rights Council. An untold number of people still living in Syria suffer from untreated emotional and psychological damage.

About 70 percent of Syrians now live in poverty. Before the war began, 47 Syrian pounds bought one US dollar. The official price stands today at about 1,250 pounds. The International Committee of the Red Cross reports that 30 percent of women have no income at all to support their families, and about 80 percent of Syrian youth struggle to afford food.

An entire generation of Syrian children faces an uncertain future. In 2017, a report from the International Rescue Committee found that a third of Syria's children don't go to school. Of those who continue their studies, half of middle school-aged children were unable to read at a second-grade level, and nearly 60 percent couldn't solve a second-grade math problem.

Then there's the physical wreckage. Today's Syria lies beneath millions of tons of rubble. Roads, bridges, schools, and hospitals have been destroyed, and there's little money to rebuild them.

And Assad, who tested positive for COVID-19 this week, remains in charge...

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