U-S President Donald Trump spent around three and a half hours on the ground in Iraq on his first visit to a troubled region.
In a speech to troops at a base in western Iraq, Trump defended his decision to withdraw forces from neighbouring Syria.
That decision prompted the resignation of Defence Secretary Jim Mattis, who did not travel with Trump and was working in his Pentagon office on Wednesday.
First lady Melania Trump was on the trip.
So was his national security adviser, John Bolton, but no other top officials or members of Congress were along.
Trump met with U.S. diplomats and senior military leaders and wished troops a happy holiday.
In his speech, he said the 2,000 U.S. troops in Syria could return home because of military gains against the Islamic State group.
The U.S. still has more than 5,000 troops in Iraq supporting the government as it continues the fight against remaining pockets of resistance by ISIS militants.
ISIS has lost a significant amount of territory in Iraq and Syria, but is still seen as a threat.