U.S. forces withdrew from Iraq in 2011. But they’re being drawn back in.

The Defense Department says that 4,087 U.S. troops are officially deployed in Iraq to fight the Islamic State of Iraq and the Levant (ISIL), but many experts believe there are more on the ground. And on Tuesday, a Navy SEAL became the third U.S. service member to die fighting ISIL.

The stakes are growing higher for the U.S. — not only because of rising troop levels, but also because of the threat ISIL poses globally.

Defeating the metastasizing terrorist organization may have become more difficult since Saturday, when growing political instability boiled over in Iraq. Protesters loyal to Shiite cleric Muqtada al-Sadr breached concrete barriers surrounding the Green Zone — the site of elite Iraqi institutions and foreign embassies — and ransacked portions of Iraq’s Parliament building. Al-Sadr’s supporters soon withdrew, but some menacingly promised a return.

The events further shook confidence in the shaky rule of Prime Minister Haider al-Abadi, whom the U.S. backs as a more reasonable alternative to the irresponsible rule of former Prime Minister Nouri al-Maliki.

Al-Abadi’s promise of a cabinet shuffle and other reforms to curb corruption has been resisted by some in Parliament.

Al-Sadr’s ostensible motive was to push for the reforms. But it was also a show of his political clout, a dynamic displayed during the Iraq war when militias loyal to the Al-Sadr family fought against U.S. forces.

This schism between Shiites comes amid even deeper sectarian divisions in Iraq that already complicate the campaign against ISIL. U.S. options are relatively limited, unless President Obama or his successor decide to rapidly ramp up U.S. troop levels — an option that seems to have little domestic support.

The administration displayed its support for Al-Abadi with recent unannounced trips by Secretary of Defense Ashton Carter and Secretary of State John Kerry, as well as Vice President Joe Biden’s surprise visit to Baghdad just days before the chaos. The high-level attention is in anticipation of an offensive against ISIL in Mosul. While there have been some gains against ISIL, momentum may be slowed by the turmoil — or stopped if Al-Abadi falls.

The best-case scenario is if Al-Abadi channels the protesters’ rage to complete his reforms. And there’s some sense that the dramatic optics might overstate the threat to Iraq’s stability, said Michael Knights, an Iraq defense expert who is a fellow at the Washington Institute for Near East Policy.

“These events have shocked Iraqis even, but they fit broadly within politics in Iraq and the fabric of the country remains unchanged,” Knights told an editorial writer, citing no interruptions in the fight against ISIL, oil production and basic government functions. “It looks very irregular to us, but Iraq is a very irregular place.”

Americans are fighting — and dying for — this irregular place, and U.S. policymakers should use recent events to push for further reforms that will help to convince Iraqis to fight fiercely for their own country’s future.