The Damascus suburbs are a smoldering ruin. Scroll through video footage and pictures of Daraya, Arbeen, Harasta, Jobar and Douma, and you will see just how worn out these areas have become. Syrians who once lived in these towns have lost everything, including their lives; if they had the means to smuggle themselves and their families out, then they were fortunate enough to only lose their homes and businesses. Damascus, the seat of political power, is too important for Bashar al-Assad’s regime to give up—and the Syrian army has demonstrated how far it will go to keep Damascus under government control.

The Ghouta region, a short thirty-minute drive from the presidential palace, is the only major area near Damascus left in rebel hands. Every other suburb has been cleared out by the regime through a combination of indiscriminate aerial bombardment, chemical-weapons attacks and siege warfare. Ghouta itself has been surrounded by pro-government forces since 2013, the year Assad’s troops fired a volley of ground-to-ground, sarin-tipped missiles in the dead of night, killing upwards of 1,400 people, according to U.S. intelligence community assessments. A minuscule amount of food gets in, the sick and seriously injured are blocked from going to hospitals, and medical supplies are stopped at the government’s lines. All the while, airstrikes and bombings continue to target everything in sight: markets, homes, hospitals, rescue workers, ambulances, and even people stepping out of their basement shelters for a breath of air.

All of this violence is distressing to say the very least. The last week has been especially terrible for the four hundred thousand civilians trapped in Ghouta; since the regime began its offensive on February 18, close to six hundred people have been killed and about two dozen clinics or hospitals have been wiped out or damaged. A journalist on the ground inside Ghouta told Al-Jazeera that it’s too difficult to keep tabs on all the massacres happening around them. UN Secretary-General António Guterres has called Ghouta “hell on earth,” hoping that desperate pleas for action will push the UN Security Council to be more aggressive. Others, like the UN’s top human-rights official, have given up on the council altogether.

The situation is getting out of control, which is why calls in Washington for forceful action by the United States are getting louder. Ambassador Fred Hof, President Barack Obama’s former Syria coordinator at the State Department, wrote last week that the Trump administration should consider using military force to deter further atrocities. “The administration’s principled response to the April 2017 sarin massacre proved . . . that steps could be taken well short of provoking World War III,” Hof remarked. Evelyn Farkas, a deputy assistant secretary of defense for Russia, Ukraine and Eurasia in the Obama administration, seconded Hof’s recommendation in the Atlantic this week, writing “[t]he United States cannot sit and watch a slow-motion Rwanda unfold.” Just as Washington stopped Serbian leader Slobodan Milosevic from continuing his ethnic cleansing campaign in the Balkans, she explained, Washington can ensure a UN ceasefire is implemented by threatening—and if necessary, using—military force against the Assad regime if it fails to comply.

These recommendations come from a good place. Like many Americans, dedicated and professional public servants like Hof and Farkas cringe when they watch the raw footage of regime bombing on their computer screens. There is nothing noble or brave about how Assad has been fighting this war—his strategy can be summed up as burning Syria in order to keep control of it.

But the United States doesn’t have the luxury of allowing emotion to be the foremost element in determining a sensible foreign policy. There is nothing sensible about throwing more bombs at the problem and setting the United States on a third regime change venture in the Middle East in the last fifteen years—two of which, in Iraq and Libya, didn’t work all that well for Iraqis, Libyans, or Americans.

Proponents of employing force against Assad to stop the killing want us to believe that this policy is both the right thing to do and easy to execute. Scramble the bombers; drop some five-thousand-pound bombs on Syrian airfields to crater the runways and destroy the aircraft; launch a couple hundred Tomahawk cruise missiles towards Syrian army garrisons and their Shia militia allies; and make it clear to Damascus that more bombing will occur if it violates UN Security Council resolutions. Bashar al-Assad will take the hint and Russian president Vladimir Putin will rethink his Syria policy.

In the real world, a humanitarian military intervention is more complicated, risky, and far from a sure thing.

How would Moscow and Tehran react if United States attacked the very proxy they have armed and supported over the past seven years? What would their response be if a U.S. airstrike killed Russian and Iranian troops? Would Assad simply stop bombing civilians after the initial strike, or would he call America’s bluff, betting that U.S public support for more strikes will prevent Trump from proceeding? How far, in other words, is Washington prepared to go?

How can the United States be sure moderates rather than extremist rebel groups would benefit from a weakened Syrian army? Is the Trump administration willing to back Bashar al-Assad into a corner like a caged lion and risk the dictator unleashing the rest of his sarin nerve gas on civilians? Would Vladimir Putin use a U.S. strike as an excuse to escalate himself, perhaps by flying in more Russian aircraft to compensate for the Syrian planes that were lost? Is it possible Moscow would respond in a different theater, perhaps by increasing the conflict in Eastern Ukraine or by testing NATO’s eastern defenses in the Baltics? Maybe more cyberattacks on the American political system would be an option—it is, after all, an election year.

How many civilians would die in a hypothetical U.S. operation? Wouldn’t civilian deaths provide the regime with the propaganda it was looking for? And even if Moscow and Tehran did blink and were scared into making credible offers at the negotiating table in Geneva, do Putin and Supreme Leader Ali Khamemei have the power to coerce Bashar al-Assad into accepting a diplomatic resolution? What if Assad declines to compromise and, with nothing to lose, chooses to fight it out to the last man. How many Syrians would die then?

Advocates of the 1995 Bosnia scenario would be quick to dismiss all of this as an excuse to do nothing. But the Slobodan Milosevic is not Bashar al-Assad, and Serbia of 1995 is not Syria of 2017; the former was a crackpot dictator with no foreign-military support, while the latter is a crackpot dictator who has Russia, Iran, chemical weapons, and tens of thousands of hardened Shia militia fighters on his side. Twenty-three years ago, Washington was the center of gravity with no serious geopolitical competition. Today, the United States operates in an increasingly multipolar world, a country that has gone through the regime-change business before with nothing to show for it except tens of thousands of American casualties and a national debt that would make even the impulsive shopper blush.

In the 1990s, an American president could order a military operation and be comfortable that the blowback would be manageable. Today, after sixteen years of making one foreign-policy mistake after another, the commander-in-chief cannot afford to ignore the hard questions and let emotions dictate when to take the country to war. As terrible as the images in Syria are—and they are terrible—the United States needs to think long and hard before setting itself on a mission that could very quickly descend into a military entanglement.

Daniel DePetris is a fellow at Defense Priorities.