WASHINGTON – U.S. troops may have driven the Islamic State from a swath of territory in Syria – allowing President Donald Trump to declare mission accomplished Tuesday – but experts said America’s yearslong involvement in Syria ended in near-complete failure.

Syria’s brutal dictator, Bashar Assad, remains in power despite U.S. demands for his ouster. The death toll from Syria’s unresolved civil war continues to mount, and millions of refugees are displaced. Russia and Iran’s influence in Syria has grown, while U.S. leverage has diminished. And though the Islamic State, also known as ISIS, may not have a patch of land to call its own, the terrorist group remains a threat in the region.

“We empowered Russia, we empowered Iran, we discredited the U.S. in terms of its ability to support the Arabs (fighting Assad) and its credibility on the ‘red line’ involving gas warfare,” said Anthony Cordesman, a national security and defense expert with the Center for Strategic and International Studies, a Washington think tank.

“We are leaving an extremely unstable Syria, and we have no clear strategy announced for what we’re doing in (neighboring) Iraq,” where the Islamic State also has a significant presence, said Cordesman, a onetime national security adviser to Sen. John McCain, R-Ariz., and former Defense Department intelligence official. “That is obviously a very undesirable way of trying to shape the future.”

Cordesman and others said the United States never had a clear strategy for its involvement in Syria, starting with President Barack Obama’s decision to launch airstrikes in 2014 and continuing into Trump’s tenure. Although both presidents said they wanted Assad out, neither aggressively pursued that goal.

“We lightly pursued a regime change policy by helping the weakest side of a civil war, and I don’t think that ever made sense,” said Benjamin Friedman, policy director at Defense Priorities, a libertarian-leaning foreign policy advocacy group.

Obama’s ‘red line’

Obama was reluctant to get involved in a new Middle East conflict after having campaigned on withdrawing from Iraq and Afghanistan. But he dispatched special operations forces to the region in 2015, and the U.S. military footprint grew to approximately 2,000 troops in Syria.

Even before American boots hit the ground in Syria, Obama warned Assad’s regime not to cross a “red line” by using chemical weapons against his own people. In 2013, Assad’s forces unleashed a sarin gas attack that killed as many as 1,400 people.

Obama prepared for a military strike but could not muster enough support in Congress for authorization. Instead, Secretary of State John Kerry worked with Russia to remove Assad’s chemical weapons stockpile. The result: Although 600 metric tons of chemical weapons were destroyed, the Assad regime has continued to use such weapons in the conflict, with horrific consequences.

Sen. Bob Menendez, D-N.J., the top Democrat on the Senate Foreign Relations Committee, said Obama missed an opportunity to arm moderate Syrian rebels who could have ousted Assad and bolstered America’s strategic interests in the region.

“The time came and went when we could actually do something like that,” he told USA TODAY on Tuesday. Neither Obama nor Trump was willing to use American power to help end the humanitarian crisis or to challenge Russia and Iran as they stepped into the void, he said.

Over the past two years, the Trump administration has articulated an evolving set of goals in Syria: defeating the Islamic State, ending Syria's civil war, protecting the allied Kurdish and Arab forces and forcing Iran and its proxy fighters out of Syria. Senior administration officials – including Trump's national security adviser John Bolton – said the United States would remain until those objectives were achieved.

But Trump's announcement Wednesday that he ordered all troops home immediately essentially short-circuited his own administration's policy.

“We have never had a very clear strategy and vision about Syria other than to say that Assad can’t stay,” Menendez said. “Now we’re at the end of it where everything we said we didn’t want has happened. Assad is in power, Russia is empowered in a part of the Middle East that it didn’t have a foothold in before, and Iran has a foothold to attack Israel. It’s a bad result all the way around.”

Menendez and other lawmakers said Trump's decision to withdraw U.S. forces is yet another misstep. It will sow further chaos in the region, they said, and leave the Kurdish forces who fought alongside U.S. troops vulnerable to attack from Assad and Turkey. Worst of all, some suggested, the Islamic State has an opportunity to re-emerge.

"The biggest winners are going to be Iran, ISIS (and) Assad," said Sen. Lindsey Graham, R-S.C. "The biggest losers are going to be the people of Syria, eventually Americans if ISIS comes back ... our allies."

Cutting U.S. losses

Others said Trump's decision would cut American losses before things got even worse.

The rationales to stay are "awful," said Friedman, who argued that the United States should embrace its defeat of the Islamic State caliphate in Syria and "not stick around long enough" to become more deeply embroiled in the conflict, particularly with Russian forces propping up the Assad regime.

"The consequences of getting into a fight with Russia are not just terrible. They’re essentially catastrophic," he said.

One thing liberals, conservatives, and centrists can agree on: U.S. involvement may have made Syria’s civil war worse – not better.

“America’s military presence in Syria has always been too little to make a decisive difference but just enough to prolong the fighting," said Sen. Chris Murphy, D-Conn., a member of the Senate Foreign Affairs Committee. "Our halfhearted military commitment made no sense from the start – we went into this war without legal authorization or realistic objectives and discounted the American people’s clear aversion to getting involved in another quagmire in the Middle East."

Justin Logan, director of programs at Catholic University's Center for the Study of Statesmanship, agreed that the U.S. role seemed to extend a conflict Assad was guaranteed to win.

"The country has been turned into a charnel house," he said. "There’s an awful lot of carnage for not that much payoff."

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