He trained as an eye doctor. He likes high-tech gadgets and country music. And he may turn out to be one of the most barbarous political leaders of the 21st century.

The blood-soaked regime of Syrian President Bashar Assad – a tall, shy and, by all accounts, unlikely inheritor and conservator of Syrian sovereignty – has survived nearly a decade of political rebellion, virulent insurgency and international condemnation.

Assad has held on to power even as other despots in the Middle East fell, as world leaders aggressively pushed for his ouster and as the Syrian people begged for peace.

March 15 marked nine years since protests in Syria calling for democratic reforms and greater freedoms sparked a civil war that has spilled far outside its borders.

What began as a hopeful uprising ballooned into a devastating and intractable conflict that contributed to the most severe refugee crisis since World War II. Syria's war has led to hundreds of thousands of deaths, displaced millions and helped spur the rise – and then entrenchment – of the Islamic State terrorist group.

It has also drawn the United States, Iran, Israel, Russia and Turkey into a complicated and potentially dangerous confrontation that lacks coherent Western oversight.

The story of Assad's survival – and Syria's disintegration – is part personal inhumanity, part international indifference. Five years ago, Assad admitted in a televised address that his army was tired and that his military was losing ground.

Now, most of Syria is back under Assad’s control as his military and its Russian allies pound the remaining patch of rebel-held territory into submission, although some well-connected Syrians living in exile believe Assad's rule is coming apart at the seams.

"He's a survivor. He's very, very tough," said Robert Ford, who was U.S. ambassador to Syria from 2011 to 2014 and engaged with Assad as part of that role. Ford described Assad as someone who "grew into the role" of butchering his own people.

According to the United Nations, humanitarian groups and Syria watchdogs, Assad's violence has taken many forms: imposing starvation sieges on rebel-held areas; repeatedly bombing, with Russian assistance, hospitals and civilian infrastructure; arresting and torturing thousands of activists, bloggers and civilians, then holding them at secret prisons deep underground, where they languish without trial. He has also allegedly used chlorine bombs and sarin gas – chemical weapons – against opposition fighters, killing children and civilians.

"Everybody who knows Assad knows two things about him," said Ayman Abdel Nour, a former friend of Syria's leader from their college days studying medicine in Damascus. "First: He lies – about everything. Second: He's extremely jealous. If you have a nice watch or camera, he will be sure to go out and get a better one the next day."

The Syrian government has consistently denied all the allegations lobbed at Assad by the West, opposition groups and by former regime insiders, such as Nour, who fled Syria in 2007 after Assad threatened to imprison him because of an online magazine he ran called "all4syria" that was critical of the regime. Assad's allies say the allegations reflect long-standing efforts to destabilize Syria and the wider Middle East region.

"Conspiracies, like germs, reproduce everywhere, every moment and they cannot be eradicated," Assad said in 2011. He claims to enjoy widespread support among Syrians inside and outside the country, even as he moves to crush the last pocket of resistance.

Tangled web of interests

The remaining Syrian rebel holdouts are in the Aleppo countryside and parts of neighboring Idlib province, in northwestern Syria. While the rebels are fiercely resisting, Assad's forces, backed by heavy Russian airstrikes, have sent nearly 1 million Syrian civilians fleeing toward the sealed border with Turkey,in what the United Nations fears could be the single worst displacement of the nine-year war so far.

Many fleeing families have no housing, no food or supplies, and they are dying in refugee camps from the cold, said Huzayfa al-Khateeb, a Syrian radio reporter who lives in Idlib. "There is no single town, no single area, you can live. And on the border, they are bombing us. The situation is so bad, more than I can explain to you," he said.

"The situation is fast turning into the biggest humanitarian horror story of the 21st Century," said Hardin Lang, vice president for programs and policy at Refugees International, a Washington, D.C.-based humanitarian advocacy organization.

It has also brought Turkey and Syria to the brink of all-out war and entangled regional and foreign powers in a complex web of decision-making that risks wider hostilities.

Turkey has taken in 3.6 million Syrian refugees, and President Recep Tayyip Erdogan says his country can't handle any more. Turkey has intervened in Syria in part because it wants Syrian rebels to help maintain a buffer zone in northern Syria, near the border with Turkey. Erdogan considers that essential to guarding against attacks from Kurdish separatists, which Turkey views as terrorists.

On Feb. 27, at least 33 Turkish soldiers were killed in a Syrian military airstrike in Idlib province, escalating an already tense and volatile situation.

Russia has long inflamed the conflict by doing everything in its power to prop up Assad. Russia sees the Syrian war as a way to reassert itself as an international power broker amid the Trump administration's retreat from the global stage, experts say.

"Moscow views the Syrian civil war as a foreign-influenced crisis that threatens the broader Middle East region and its interests there and at home," said Osamah Khalil, a professor of Middle East history at Syracuse University in New York.

Iran has also been drawn into the fray, supporting the Assad regime with military intelligence and training. Iran's presence in Syria and support there for Hezbollah militants has alarmed the U.S. and its most important regional ally, Israel.

"Hezbollah has a well-trained and battle-hardened militia, as well as large stocks of missiles that Israel sees as a direct threat," Khalil said.

For the past few weeks, Idlib's skies have been relatively free of Russian and Syrian government warplanes for the first time in months amid a tense calm as a cease-fire deal brokered by Turkey and Russia appears to be holding in Syria’s northwestern province.

But there are other looming complications.

Earlier this month, Turkey opened its frontiers with Greece and Bulgaria to allow fleeing Syrians and other migrants to enter the European Union – a move aimed at pressuring EU leaders to intervene in Syria amid the refugee crisis. Turkey's action revived memories of 2015,when more than 1 million asylum seekers fled to Europe from Syria, Iraq, Afghanistan and other conflict zones. It was a humanitarian train of people the continent had not witnessed since the ravages of the Holocaust.

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Meanwhile, U.S. policy toward Assad's Syria has roller-coastered from intervention and airstrikes to resignation, inattention and downright confusion. Former President Barack Obama failed to enforce his own "red line" when Assad allegedly used chemical weapons in 2013, killing as many as 1,400 Syrians, including 400 children.

President Donald Trump, before taking office, said the U.S. should "stay the hell out of Syria"and warned that Hillary Clinton, the 2016 Democratic presidential nominee, wanted "to flood our country with Syrian immigrants."

But after Trump took office he soon found himself ordering a U.S. airstrike against Syrian targets after another suspected chemical weapons attack by Assad in April 2017. (The Syrian leader has denied using such weapons.) Trump has since blasted Assad as an "animal"and blamed Obama for not acting more aggressively.

Then, last year, Trump declared victory over the Islamic State group in Syria and moved to withdraw U.S. troops from the country, a move he has partly walked back.

Does Trump want out of Syria? Apparently, not so much.

"So the idea that America must do something, I just find that to be – I don’t even see that as being a real argument," Robert O'Brien, Trump's national security adviser, said at an event in Washington, D.C., in mid-February, summing up one version of the U.S. position on Syria. "You've got Russian and Iranian and Syrian troops attacking Turks and their allies. And by the way, there are terrorists in Idlib as well. ... We’re supposed to parachute in as a global policeman and hold up a stop sign and stay 'Stop this Turkey, Stop this Russia, Stop this Iran, Stop this Syria?"

'An age of impunity'

There is effectively "no unity or even clarity over Western policymaking" with respect to Syria, said David Miliband, a former Britishforeign secretary and now head of the International Rescue Committee, a global aid relief organization based in New York.

Miliband said there is no "short-, medium- or long-term" plan about what the international community wants to achieve beyond halting the humanitarian disaster.

"That means there's no cost-benefit calculations being done by Russia or Syria or Iran over what they're doing in Syria," he said. "What we're seeing in Syria now is really an age of impunity facilitated by Western division and dysfunction."

Still, there is one constant: Assad.

Firas Tlass, at one point one of Syria's richest men and a former close confidant of the Assad family, said in a phone interview from Dubai, where he lives in exile, that there is a "mood within Syria today suggesting the regime could soon collapse, that it can't continue economically, that it's ultimately lost without real international support."

He said that while Assad may have the upper hand territorially and militarily, it changes every few months, and everyday life, even for regime loyalists inside Syria, is hard: electricity blackouts, little access to health care, few supplies at the market.

"They had hoped that the regime would make sure there was money for salaries and goods and electricity. The opposite has happened," said Nour, Assad's friend from their college days, who now lives in the U.S., where he founded Syrian Christians for Peace, a pro-opposition humanitarian organization that distributes aid inside Syria.

Nour says Assad's military gains are disguising a regime in its dying days.

"It's really hurting. The regime is suffering," said Haid Haid, an expert on Syria at Chatham House, in a panel discussion March 11 at a conference about Syria hosted by the London-based global affairs think tank.

Zaki Lababidi, a Washington, D.C.-based president of the Syrian American Council, which advocates for a secular democracy in Syria, echoed that assessment, saying Assad is "definitely not a victor." Instead: "He’s a puppet of Russia, and he presides (over) a destroyed country, a destroyed economy," he said.

"To the Syrian people, your revolution succeeded. The Assad regime is done."

But Tlass cautioned against expecting that much could be done to accelerate Assad's ouster, unless Russia or Iran decide it is time for him to go. And he noted that even if Assad is forced from power, any new Syrian government would almost certainly be filled with officials and military apparatchiks implicated in Assad's crimes.

Afraid of the sight of blood

Assad was encouraged to become a doctor by his late father, who ruled Syria for three decades as a virtual police state. Hafez Assad was brutal is his crackdowns on dissent, perpetually paranoid, corrupt and willing to murder friends to retain his grip on power.

Hafez Assad viewed his second son as temperamentally unfit to be Syria's president –awkward in company, a poor public speaker and afraid of the sight of blood, according to Sam Dagher, author of "Assad or We Burn the Country: How One Family's Lust for Power Destroyed Syria." But when his eldest son, Bassel, died in a high-speed car crash, Syria's leader, who had survived several assassination attempts and was credited with transforming his country into a regional power, turned to Bashar to succeed him.

At the time, this aloof and timid son was studying to be an eye doctor at London's prestigious Western Eye Hospital. It was a discipline he chose, Bashar Assad would later often say, according to Dagher, because ophthalmology involves little blood.

Once chosen by his father for the presidency, however, "he was on a quest to slay his inner demons," Dagher writes in his book. "Bashar set out to prove that he could be as cutthroat and ruthless as his father, if not more so."