Members of the Trump administration, including U.S. defence secretary Jim Mattis, suggested that the focus of the strike had to be narrowed down to chemical weapon sites to minimise civilian casualties and avoid an escalation with Mr Assad's backers, Iran and Russian Federation. The president of the New America Foundation, Anne Marie Slaughter, tweeted that she believes that the United States, the United Kingdom, and France did "the right thing" by striking Syria.
Defense Secretary Mattis, a retired Marine general who gained notoriety during the 2004 siege of Fallujah in Iraq, took a more reasonable stance on the strikes.
The U.S. military, along with France and Britain, fired 105 missiles against three chemical weapons facilities in Syria on Saturday.
Despite being in the area, the Cook didn't fire a shot - and it possibly served as a distraction while cruise missiles poured in from ships, submarines, and jets in an attack that the Pentagon says succeeded in that each hit.
"This is now part of their standard combat doctrine", said Gregory Koblentz, a chemical weapons expert at the Schar School of Policy and Government at George Mason University.
Both the Russians and the USA said there were no reported casualties.
The Kremlin dismissed the claims.
The claim by the OPCW comes as Russian foreign minister Sergei Lavrov was forced to deny Russia tampered with evidence at the alleged attack site.
And the Russian ambassador to the Netherlands, Alexander Shulgin, said it was a "blatant lie" that Moscow was hampering the investigation.
OPCW experts to reach Syria's Douma on April 18 - Russian defense ministry
European Union foreign ministers threatened similar measures. "I think everyone is going to feel it at this point", she added. Russian Foreign Minister Sergei Lavrov denied that Moscow had interfered with any evidence.
When asked why the US should get more involved in the situation in Syria, Eid said simply, "With great power comes great responsibility".
President Trump hailed the success of the USA -led missiles strikes on Syria Monday, boasting that the Russian military was unable to shoot down even one of the allies' missiles last weekend. "We can not allow the use of chemical weapons to become normalized".
British Prime Minister Theresa May and French President Emmanuel Macron were both due to face their respective legislatures on Monday. "Public estimates are as high as 200", she said.
France urged OPCW nations to boost the organisation's work so it can completely dismantle Syria's "secret" toxic weapons programme.
That was the pattern after the United States struck Syrian targets a year ago in retaliation for a chemical attack. Regime forces have now entered Douma and declared the entire Eastern Ghouta region around it fully retaken, ending a five-year siege and reclaiming an opposition bastion on the edge of the capital. Pentagon officials said the assault pummeled, but did not eliminate the Syrian program.
The pictures come as the global chemical arms watchdog on Monday opened emergency talks on the suspected poison gas attack in Douma, diplomatic sources told AFP.
A "number of missiles" targeted a scientific research center in Barzeh, near Damascus, and destroyed a building housing an education center and labs and caused other damage, the military said. But "strangers entered as we were in a state of chaos and spread a rumour among people there had been a chemical attack, and people became alarmed".
Mr Ryabkov told reporters in Moscow that what is hampering a swift resolution of the mission's visit to the Syrian town of Douma, near Damascus, the site of the alleged chemical attack, is "the consequences of the illegal, unlawful military action", a reference to Saturday's punitive air strikes.
Russian ambassador Shulgin repeated the accusations telling reporters in The Hague that Douma residents had not been able to produce "a single body".