WASHINGTON — Hawkish Republican Sens. John McCain and Lindsey Graham are pressing the Trump administration to escalate military efforts to protect the Syrian people against President Bashar Assad.

"As part of a broader strategy, we urge the President to take greater military action to achieve our objectives, including grounding the Syrian air force and establishing safe havens inside Syria to protect Syrians," the senators said in a joint statement Tuesday.

"There will never be a diplomatic solution as long as Assad dominates the battlefield," according to McCain, the Senate Armed Services Committee chairman, and Graham, chairman of the Senate Appropriations Subcommittee on State, Foreign Operations, and Related Programs.

Defense Secretary James Mattis said earlier in the day the airstrike was meant to deter the use of chemical weapons, and that while there is "no doubt the Syrian regime is responsible" for an attack last week, America's priority in Syria is the fight against the Islamic State group, also known as ISIS and ISIL.

Mattis acknowledged the option of safe zones or no-fly zones is available to President Donald Trump, but said the purpose was singular. It was "not a statement that we could enter full fledged, full bore into the most complex civil war probably raging on the planet at this time."

On April 6, a U.S. strike targeted Syria's Shayrat airfield, equipment and chemical weapons in response to an April 4 chemical weapons attack the U.S. government has attributed to the Assad regime. The chemical weapons attack reportedly killed 89 people.

Russian Foreign Minister Sergey Lavrov began a meeting with U.S. Secretary of State Rex Tillerson on Wednesday warning the U.S. not to strike the Syrian regime again. Tillerson has said Russia must end its support for Assad, while the U.S. envoy to the United Nations, Nikki Haley, has said Assad should have no future in Syria.

A Politico/Morning Consult poll announced Wednesday found that revealed that voters support the initial U.S. airstrikes in Syria ordered last week by President Donald Trump — but there is less backing for an escalation of hostilities that includes ground forces.

In a sign of bipartisan support for last week's airstrikes, 66 percent of voters approve of the actions taken with 82 percent of Republicans, 57 percent of Democrats and 59 percent of independents backing the strikes. The poll also showed that 63 percent of Americans believe we should be doing more in Syria, 70 percent of Americans support imposing tighter sanctions on Syria in the international community and only 39 percent of voters support putting troops on the ground to remove Assad.

"Sixty-three percent of Americans say the U.S. should be doing more in Syria, but when we ask what concrete actions should be taken, that support falters," said Kyle Dropp, of Morning Consult. "The only action that garners widespread support is imposing tighter sanctions, which 70 percent of Americans support."

U.S. lawmakers, primarily Democrats, have urged Trump to share its strategy in Syria, while Republicans have been divided on whether to escalate militarily against Assad.

Senate Majority Leader Mitch McConnell, R-Ky., told reporters last week Vice President Mike Pence told him after the U.S. airstrike that it was related specifically to Assad's alleged use of chemical weapons.

Senate Minority Leader Chuck Schumer, D-N.Y., said his caucus is worried Trump's actions in Syria could lead to another open-ended major military fight for U.S. troops in the region and that "any further action should come to Congress" for approval. 

"There should be a defined strategy," Schumer said. "And I, for one, am really, really wary and worried about getting committed to another land war and making the same mistake that we did in Iraq."

On CNN on Tuesday, the House Armed Services Committee's ranking Democrat, Rep. Adam Smith, of Washington, said that while Assad is not the legitimate leader of Syria, and although ISIS will not be defeated as long as Assad is in charge, Smith was "not a fan of regime change."

"I want to make sure that we don't overreact in the U.S. and think that there is some military solution and think that we can go in there and go to war, not just with Syria but with Russia and Iran and not cause even more damage than is currently being caused," Smith said.  

Smith called the images of chemical attack victims said to have spurred Trump to order the airstrike "horrific," but cautioned: "We also have to be mindful of our limitations, and I think in the past, certainly in the case of Iraq, we overthought what he could do."

McCain and Graham have urged the Trump administration for a more muscular approach on behalf of the Syrian people, and a strategy that "secures U.S. and allied interests in Syria — ending the conflict, dealing a sustainable defeat to ISIL and Al-Qaeda, and beginning to repatriate Syrian refugees to their homes."

Note: The original story was updated to include the Morning Consult/Politico poll results.

Email:  jgould@defensenews.com                         

Twitter:  @reporterjoe

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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