The Pentagon ordered dozens of cruise missiles launched against an airfield in central Syria late Thursday in retaliation for a gruesome poison gas attack this week that U.S. officials said was carried out by President Bashar Assad's forces.
President Trump authorized the attack, the most significant military action of his 11-week presidency, after he was briefed by Defense Secretary James N. Mattis in Palm Beach, Fla., where the president is hosting Chinese President Xi Jinping.
"Assad choked out the lives of helpless men, women and children," Trump said in a televised statement from his Mar-a-Lago retreat. "Even beautiful babies were cruelly murdered in this very barbaric attack. No child of God should ever suffer such horror."
"Tonight I ordered a targeted military strike on the airfield in Syria from where the chemical attack was launched," he added. "It is in this vital national security interest of the United States to prevent and deter the spread and use of deadly chemical weapons."
The attack marks the first time the U.S. has deliberately targeted Assad's military in Syria's multi-sided civil war, now in its seventh year. Until now, the U.S. has focused only on targeting Islamic State militants.
It marked a violent and abrupt reversal of Trump's previous hands-off stance toward Assad.
In effect, Trump was carrying out the policy that his predecessor, Barack Obama, had nearly executed, but backed away from, in the fall of 2013 after an even more deadly chemical weapons attack on civilians.
At the time, Trump had publicly urged Obama not to strike, saying that to do so without congressional approval would be a mistake.
But people who have spoken to Trump say he was deeply affected by the images of children choking to death as a result of the attack, which Turkish medical authorities, who treated many of the victims, said involved sarin nerve gas.
Trump said in a brief news conference this week that the attack had caused him to change his views about Assad.
"That crosses many, many lines," Trump said Wednesday. "Beyond a red line — many, many lines."
The strike was carried out by two Navy destroyers patrolling in the eastern Mediterranean Sea, which fired roughly 60 Tomahawk cruise missiles from hundreds of miles offshore, well out of range of Syrian air defenses, officials said.
The Porter, a destroyer that launched Tomahawk missiles during the opening stage of the 2003 invasion of Iraq, is in the region, along with the guided missile destroyer Ross.
The target was a military airfield, Shayrat, northeast of Damascus, that U.S. officials said was used to launch the lethal gas attack in Idlib Province on Tuesday. The field has two runways and a series of hardened shelters.
Targets included aircraft, fuel and weapons depots, and command and control facilities, officials said. Pentagon officials said they were assessing the results of the strikes, which hit the base before dawn Friday in Syria.
The strike was designed to be limited in nature and to damage facilities with minimal casualties, the officials made clear.
"Every precaution was taken to execute this strike with minimal risk to personnel at the airfield," Capt. Jeff Davis, a Pentagon spokesman, told reporters. "The strike was a proportional response."
The Russian military, which operates from the Shayrat base, was warned ahead of time, Davis said, and the area that the Russians are known to have used was carefully not targeted.
The U.S. has no plans for additional strikes for now, he added.
"It will be the regime's choice if there are any more" military strikes, Davis said. "And it will be based upon their conduct going forward. We do not tolerate the use of chemical weapons against innocent civilians."
A "military source" in Syria confirmed the missile strike by the U.S., the Syrian Arab News Agency reported. "One of our air bases in the central region at dawn today was hit with a missile strike by the United States of America, which led to losses."
It said the attack followed a "propaganda campaign launched by a number of countries" following the incident in Khan Sheikhoun.
The action drew mixed responses from leaders of both parties in the U.S., who have been deeply divided over Syria policy nearly for the length of the country's civil war.
Members of Congress who have long argued for more direct U.S. military action against Assad, including Republican Sens. John McCain of Arizona and Marco Rubio of Florida, hailed the attack.
House Speaker Paul Ryan (R-Wis.) said the strike "was appropriate and just."
"These tactical strikes make clear that the Assad regime can no longer count on American inaction as it carries out atrocities against the Syrian people," he said.
Hillary Clinton, whom Trump defeated in the presidential election, said in an appearance in New York several hours before the strikes were launched that she had long advocated attacking Syria's airfields.
But other Democrats chided Trump for acting without Congress' approval.
So did Sen. Rand Paul (R-Ky.). "While we all condemn the atrocities in Syria, the United States was not attacked," he said.
"The President needs Congressional authorization for military action as required by the Constitution, and I call on him to come to Congress for a proper debate."
"Our prior interventions in this region have done nothing to make us safer, and Syria will be no different," he said.
Pentagon officials updated their Syria plans after an emergency meeting of the National Security Council late Wednesday, one day after U.S radar and surveillance systems detected a fixed-wing Syrian aircraft drop bombs near a hospital in the rebel-held area around Khan Sheikhoun in Idlib province, officials said.
Soon after the attack, photos and videos emerged on social media that showed lifeless bodies of children, eyes open, sprawled on the ground beside surviving victims with foam bubbling from their mouths as they gasped for air.
The Joint Chiefs of Staff met Thursday afternoon to consider the crisis and top congressional officials were briefed on the plans. The White House national security advisor, H.R. McMaster, was in Palm Beach with Trump.
Whether the strike Thursday will seriously affect Syria's capabilities remains to be seen.
Airstrikes on the runways that Syrian forces use to launch bombing missions would have only temporary, minimal impact, experts said.
Helicopters, which Syrian troops have used to drop improvised "barrel bombs" on civilian targets, can fly from almost anywhere.
Complicating the calculus, more than 1,000 U.S. troops now are deployed in Syria. Many are helping Syrian rebel militias fight against Islamic State, especially as they close in on the group's stronghold at Raqqah.
The U.S. attack could make the Americans targets for retaliation from Syrian troops.
In any case, a "one-off strike" would have no real impact, said Frederic C. Hof, a former Obama administration advisor on Syria and director of the Rafik Hariri Center for the Middle East at the Atlantic Council in Washington.
"It's basically telling Assad 'Do what you want to civilians, just not with chemicals,'" he said. "We'll go back to where we were in 2013."
Any attack needs to be coupled with a diplomatic effort to get Russia to rein in Assad's targeting of schools, marketplaces, and apartment blocks, Hof said, adding that "otherwise, Assad will return to business as usual."
The options in Syria also have become more complex since 2015 because Russian and Iranian forces have poured in to help Assad. Any broader attack on his forces risks a confrontation with Russia, a nuclear-powered rival that Trump had hoped to recruit for the fight against Islamic State.
There were indications that the administration was losing patience with Russia.
"It is very important that [the Russians] consider carefully their continued support for the Assad regime," Secretary of State Rex Tillerson told reporters.
Tillerson added there was "no doubt in our minds" that Assad's government was responsible for the poison gas attack. He said there is "no role" for Assad in Syria's future, reversing the position he had expressed last week.
Tillerson will visit Moscow next week. Although the trip was previously planned, it will focus in part on Russia's continued support for Assad, officials said Thursday.
Tillerson called his Russian counterpart, Sergei Lavrov, on Wednesday to hear Russia's version of the Syria attack, a senior State Department official said.
Moscow has backed Assad's claims that Syrian forces were not responsible, saying the toxic gas was released in an airstrike on a rebel storage facility.
At the United Nations Security Council, a draft resolution by the United States, France and Great Britain that condemns Assad was revised slightly on Russian insistence.
But Russia is likely to veto it, as it vetoed previous measures against Syria's use of chemical weapons.
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8:55 p.m.: The story was updated with comments from the Syrian Arab News Agency.
8:25 p.m.: The story was updated with further details from the Pentagon.
7:25 p.m.: The story was updated with comments from President Trump.