President Joe Biden said the US would not hesitate to use its military power against terrorist threats even though the Afghanistan war is over, in remarks at a ceremony marking the 21st anniversary of the Sept. 11, 2001 attacks.

“We’ll continue to monitor and disrupt those terrorist activities wherever we find them, wherever they live, and we’ll never hesitate to do what’s necessary to defend the American people,” Biden said Sunday speaking at the Pentagon.

“It took 10 years to hunt down and kill Osama bin Laden but we did,” the president added. He also cited the July airstrike he ordered that killed al-Qaeda leader Ayman al-Zawahiri, the successor of bin Laden.

Biden laid a wreath at the military headquarters outside Washington, where American Airlines Flight 77 crashed on the morning of the attack, killing 184 people. First lady Jill Biden is participating in an observance at the Flight 93 National Memorial in Shanksville, Pennsylvania. It has been an annual tradition for US presidents to attend memorial events to mark the deadliest terror attack on American soil.

“It’s not enough to stand up for democracy once a year or every now and then. It’s something we have to do every single day,” Biden said.

This year’s anniversary comes roughly a year after the US withdrawal from Afghanistan, where the nation’s military became bogged down in a two-decade-long war after invading in the aftermath of the 9/11 attacks. Biden came under withering criticism for the chaotic nature of the pull-out, shaking Americans’ confidence in his ability to govern.

Biden’s approval rating has rebounded in recent weeks amid a series of victories on domestic and foreign policy.

Vice President Kamala Harris and Second Gentleman Doug Emhoff attended a commemoration ceremony at the World Trade Center site in New York.

This year’s observance in New York comes as the city grapples with the lingering economic effects of the Covid-19 pandemic. Unemployment remains high, and some of the city’s biggest economic drivers -- office workers and tourists -- haven’t returned in full force.

But the city is starting to show signs of improvement. Covid restrictions are largely over, with New York Governor Kathy Hochul ending the mask mandate on public transit on Wednesday.