The US is withdrawing from Iraq after two decades. The withdrawal could provide room for the resurgence of ISIS

U.S. forces are set to withdraw from their last bases in Iraq by Wednesday, a departure celebrated as a victory by Iran and its allies, who now wield profound influence in the country where 4,500 Americans lost their lives during more than two decades of war.

Iranian security experts say the withdrawal—agreed in 2024 under the presidency of Joe Biden and implemented by Donald Trump’s administration even as it wages war against Iran—could give Tehran and its powerful allies free rein, while also allowing other U.S. adversaries to return in force, including the Islamic State (ISIS).

“Iran will benefit strategically from the coalition’s departure, as it removes a military presence that, for years, acted as a counterweight to Tehran’s influence in Iraq,” said Jasim al-Bahadli, an Iraqi security analyst specializing in the study of Iran-aligned Shiite armed groups.