Iran-led push to retake Fallujah from ISIS worries U.S.

The battle over Falluja has evolved into yet another example of how United States and Iranian interests seemingly converge and clash at the same time in Iraq. Both want to defeat the Islamic State, also known as ISIS or ISIL. But the United States has long believed that Iran’s role, which relies on militias accused of sectarian abuses, can make matters worse by angering Sunnis and making them more sympathetic to the militants.

While the battle against the Islamic State straddles the borders of Iraq and Syria, the United States has approached it as two separate fights. In Syria, where the government of Bashar al-Assad is an enemy, America’s ally is the Kurds.

But in Iraq, where the United States backs the central government, and trains and advises the Iraqi Army, it has been limited by the role of Iran, the most powerful foreign power inside the country.

That United States dilemma is on full display in Falluja as the fighting intensifies.