WASHINGTON (AP) — President Donald Trump on Monday marked the fourth anniversary of the suicide bombing that killed 13 U.S. service members during the chaotic withdrawal at the end of the Afghanistan War by signing a proclamation honoring the fallen.

Surrounded by about 35 family members of those killed, including one wearing a “Make America Great Again” cap, Trump used the somber occasion to decry his predecessor, Democratic President Joe Biden, for allowing the attack to happen.

Tuesday is the anniversary of the bombing that also killed more than 100 Afghans at Abbey Gate outside the Kabul airport on Aug. 26, 2021. Trump called it “one of the dumbest days in the history of our country by the previous administration.”

“That was a terrible day,” Trump said. “And I think it was the worst day, and in many ways the most embarrassing day, in the history of our country.”

Biden’s White House was following a withdrawal commitment and timeline that the Trump administration had negotiated with the Taliban in 2020. A 2022 review by a government-appointed special investigator concluded decisions made by both Trump and Biden were the key factors leading to the rapid collapse of Afghanistan’s military and the Taliban takeover.

Trump made the suicide bombing and Biden’s handling of it a frequent topic as he campaigned for president. The relatives of some of the U.S. service members killed also appeared on stage at the Republican National Convention in July 2024.

On the third anniversary of the attack, Trump was invited by family members of some suicide bombing victims to Arlington National Cemetery’s Section 60, a hallowed section where U.S. forces killed in the Iraq and Afghanistan wars are buried.

That became a flashpoint after a staffer from Trump’s campaign reportedly shoved a cemetery employee who was trying to prevent the photographing of a ceremony honoring the service members killed in the Afghanistan War withdrawal. Federal law prohibits campaign or election-related activities within Army national military cemeteries.

In a statement marking the third anniversary of the attack, Biden called the 13 Americans who died “patriots in the highest sense” who “embodied the very best of who we are as a nation: brave, committed, selfless.”

“Ever since I became Vice President, I carried a card with me every day that listed the exact number of American service members who were killed in Iraq and Afghanistan — including Taylor, Johanny, Nicole, Hunter, Daegan, Humberto, David, Jared, Rylee, Dylan, Kareem, Maxton, and Ryan,” Biden said in a statement in August 2024.

Also on hand for Monday’s proclamation signing were Defense Secretary Pete Hegseth and Vice President JD Vance, who told victims’ relatives that Trump’s action was “a rectification of a wrong” because Biden “lost your loved ones through incompetence” and his government “never actually put pen to paper to say we’re grateful for your sacrifice.”

Trump has ordered a new Defense Department review of what occurred during the withdrawal of U.S. forces, and Hegseth said he expected that to be complete by the middle of next year.

“The military needs to answer for what happened in Afghanistan,” Hegseth said.