Asked why the president had acted now, given the Assad government is alleged to have used chemical gas at least 50 times, administration officials said they believed there was "incontrovertible evidence" that chemical weapons had been deployed.
In the wake of last weekend's attack, some US officials advocated a larger strike than the limited action Trump ordered in April 2017, also in response to suspected chemical weapons use. Those assertions have been denounced as lies by Western officials.
Russian Federation and Syria have denied that chemical weapons were used at all and said their own investigators had been to the area and found no trace of them.
The second and third targets were part of what the USA military described as the Him Shinshar chemical weapons complex outside the city of Homs.
She wrote: "Syria's use of chemical weapons is sickening but the question the PM has not answered is how this action, taken without parliamentary approval, will halt their use or bring long-term peace".
Trump has made clear he wants to withdraw the roughly 2000 U.S. troops involved in the anti-Islamic State campaign in Syria.
Britain and France joined the United States in the strikes in a coordinated operation that was meant to show Western resolve in the face of what the leaders of the three nations called persistent violations of worldwide law.
It is natural that many Americans would be skeptical of the US intelligence community's confirmation that Assad used chemical weapons in an attack that killed dozens of Syrian civilians, including children, several days ago. "Who gave them the right to attack?"
"I suspect, however, they'll think long and hard about it", he said.
"The legal basis. would have to be self-defence or the authority of the U.N. Security Council".
One site hit by the barrage of missiles was the Bazrah Research Center, a scientific research center on the outskirts of Damascus.
Sablin also said Assad accepted an invitation to visit the Siberian region of Khanty-Mansi in Russian Federation.
The Trump Administration, meanwhile, indicated that the predawn assault was a one-off operation to be repeated only if Assad used chemical weapons again.
"A perfectly executed strike last night".
The Syrian government has to declare the entire stockpile of chemical weapons in order to resume the political dialogue in Geneva, US State Department Spokeswoman Heather Nauert said.
But it also noted a "residual" element remained.
Syria released video of the wreckage of a bombed-out research lab, but also of Assad arriving at work as usual, with the caption "Morning of resilience".
"If the Syrian regime uses this poison gas again, the United States is locked and loaded".
"This operation does not represent a change in U.S. policy, nor an attempt to depose the Syrian regime". "All the things that we need to live are being cut", he said.
Russian and Iranian military help over the past three years has allowed Assad to crush the rebel threat to topple him. They came from the Red Sea, the Arabian Gulf and the Mediterranean, homing in from three directions to overwhelm whatever missile defenses Assad's regime might employ.
Kuwait has followed up with deep concern the latest military operations in Syria, Xinhua reported citing the Kuwait News Agency (KUNA) which quoted a ministry source as saying on Saturday.
US President Donald Trump announced on Saturday that the US-led strikes in Syria were a "mission accomplished", adding that he had no intention of launching further strikes against President Bashar al-Assad's targets.
In conjunction with British and French soldiers, the USA military carried out the strikes on three sites, a scientific research center near Damascus and two chemical weapons storage facilities near Homs.
And, like Pence, U.S. Ambassador to the United Nations Nikki Haley emphasized that the United States is ready to keep pressure on Syria following military strikes that targeted the country's ability to use chemical weapons. Moscow condemned the Western states for refusing to wait for their findings. Russian Federation and Syria denied this, saying the incident was either fabricated or was a false-flag attack.
But Johnson stressed the "overwhelming purpose" of the mission was a response to a series of chemical attacks in recent years.