Four Americans were killed in a suicide bombing in Manbij, Syria on Wed., Jan. 16. ISIS took responsibility for the attack.

A military convoy was at a restaurant that they often ate at during patrols in Manbij. A nearby attacker wearing an explosive vest blew himself up. 19 people were either killed or wounded, including two service members, a Pentagon civilian and a US contractor.

About a month before the bombing, President Donald Trump declared that American troops would be removed from Syria because the US had defeated ISIS in the area. Mike Pence’s statement about American troops leaving the area was quoted in a New York Times article.

“As we begin to bring our troops home, the American people can be assured, for the sake of our soldiers, their families and our nation, we will never allow the remnants of ISIS to re-establish their evil and murderous caliphate — not now, not ever,” Pence said.

Critics of Trump believe that the attack might have been encouraged by Trump’s decision to remove forces. In 2011, when the US started withdrawing troops from Iraq, violent attacks increased.

Lindsey O. Graham, Senator of South Carolina, was quoted in a Washington Post article. He is concerned that Trump’s statement evoked Syria’s interest for carrying out the bombing.

“You make people we are trying to help wonder about us, and as they get bolder, the people we’re trying to help are going to get more uncertain,” Graham said. “I saw this in Iraq, and I’m now seeing it in Syria.”

Now after the attack, many are questioning if it is still the best idea to remove US troops from Syria. Several state leaders have encouraged Trump to keep Americans in Syria because ISIS hasn’t been destroyed.

“Every American wants our troops to come home, but I think all of us want to make sure that when they do come home, we’re safe,” Graham said in a CNN article. “So I would hope the President would look long at hard at where he’s headed in Syria. I know people are frustrated, but we’re never going to be safe here unless we’re willing to help people over there who will stand up against this radical ideology.”

Thus far, the withdrawal of troops hasn’t been anything more than military equipment. American forces could still be in Syria months or even years from now. As of yet it is unclear of how Trump will handle the situation.