Foreign ministers of the United States, Britain, France and Germany arrived in Vienna for talks aimed at finding a political solution to Syria's four-year-old civil war. (Reuters)

Secretary of State John F. Kerry arrived Thursday in the Austrian capital, the scene of his last diplomatic success, spearheading an effort to end what he has called the “nonstop horror” of the Syrian civil war.

The hastily convened meeting of diplomats from at least 19 countries is propelled by growing alarm that the Syrian conflict is rapidly spiraling out of control and threatens regional and global security.

Kerry was cautious when asked what he expected the talks, set to open Friday, to achieve.

“I’ll tell you when we’ve accomplished it,” he said before meeting with Austria’s foreign minister, then promptly added, “If. If.”

On Thursday, Kerry held preliminary meetings with participants in the talks. In a sign of how the Syrian conflict — which is in its fifth year — has upended traditional politics, one of his first sit-downs was with Iranian Foreign Minister Mohammad Javad Zarif.

The alliance between Russia and the regime of Bashar al-Assad goes back decades. Here's a bit of historical context that explains why Russia is fighting to prop up its closest ally in the Middle East. (Ishaan Tharoor and Jason Aldag/The Washington Post)

Iran has provided military and financial backing to Syrian President Bashar al-Assad, but this is the first time it has been invited to join international talks on resolving the conflict. It also marks the first time that the United States and Iran are working together since striking a landmark nuclear deal in July in Vienna and underscores that no solution to the conflict is possible without Iran’s involvement.

Kerry spoke with Zarif about implementing the nuclear agreement and raised the issue of U.S. citizens detained or missing in Iran, said State Department deputy spokesman Mark Toner.

The nations coming together Friday in Vienna have divergent views of the role Assad should play in his country’s future.

The United States, Turkey and Saudi Arabia — as well as other Persian Gulf nations — insist that any transition period must end with Assad relinquishing power. Iran and Russia, his biggest backers, have said that they are not wedded to the idea of Assad remaining in place indefinitely. But they also maintain that without Assad, ­Syria would collapse into unacceptable chaos.

On Thursday night, Kerry met with diplomats from Russia, Turkey and Saudi Arabia.

State Department officials have said that they do not expect countries with such disparate viewpoints to agree on a solution anytime soon, but noted the urgency of advancing dialogue on ways to pull Syria out of a deep dive.

“The challenge that we face in Syria today is nothing less than to chart a course out of hell,” Kerry said in a speech Wednesday before departing for Vienna.

The increasingly urgent diplomatic push for a resolution in Syria is driven by several factors, including Russia’s role and a migrant crisis that is overwhelming Europe.

Russia began carrying out airstrikes in Syria late last month, an intervention separate from the bombing campaign by a U.S.-led coalition.

Moscow claims that its airstrikes target the Islamic State, the extremist group that controls large swaths of Syria and Iraq. The United States contends, however, that most of Russia’s bombing raids have targeted opponents of Assad, including U.S.-backed moderate rebels. Washington considers that approach counterproductive, arguing that only when Assad’s departure is ensured can Syrians unite to fight the Islamic State.

Many Syrians appear to have lost hope that any end to the fighting is near, though, and hundreds of thousands have fled to Europe to build new lives, straining governments there.

The Syrian crisis is so dire that it has brought Iran and Saudi Arabia to the same bargaining table, despite their historic regional rivalry. Their frosty relations have boiled over into overt animosity since a stampede during last month’s hajj pilgrimage in Saudi Arabia, which, Iran says, left more than 400 Iranians dead. Tehran blames the tragedy on mismanagement by Riyadh.

Some foreign policy analysts are skeptical that the Vienna meeting will achieve much, at least in the short run.

“We need to be realistic in terms of how long it would take to come to some kind of agreement between countries, since there are very sharp disagreements between them,” said Robert Ford, a former U.S. ambassador to Syria who is a fellow at the Middle East Institute in Washington.

“And even when these countries come to a broad agreement, getting Syrians on the ground — government and opposition, who have been locked in hard combat for four years — to move ahead with whatever outside actors agree upon will itself be a challenge.”

At best, Ford said, the meeting will clear a path that may lead to a resolution in the distant future.

“In the meantime, the fighting goes on, the refugee crisis continues, the Islamic State continues to operate, al-Nusra continues do things,” he said, referring to two of the Islamist militant groups fighting the Assad government. “I don’t think people should expect very much from this to happen quickly.”

Cliff Kupchan, chairman of
the Washington-based Eurasia Group, said that the gulf between the stances of the primary players in the region is likely to block immediate progress but that positions could moderate in time.

“Ultimately, there is possible overlap in views,” he said, adding, “The devil lies in the details of the composition of any transitional government, and in time a compromise could be found.”

But, like Ford, he does not expect the talks to have an immediate effect.

“Talks will be tough,” he said, “and the fighting and the refugee flows will only get worse.”

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