President Biden on Tuesday defended his decision to withdraw U.S. troops from Afghanistan, describing the frantic evacuation as an “extraordinary success” even though dozens of Americans and thousands of Afghan allies were left behind.

Biden’s remarks were passionate and defiant, reflecting his determination that ending America’s longest war was the right choice despite a wave of criticism that the departure was mishandled.

“With all of my heart, I believe this is the right decision, a wise decision, the best decision for America,” he said from the White House.

The war, he asserted, “should have ended long ago.”

Although Biden originally promised the withdrawal would be “orderly and safe,” he said Tuesday that some level of chaos was unavoidable.

“The bottom line is there is no evacuation from the end of a war that you can run without the kinds of complexities, challenges and threats we faced,” he said. “None.”

The last U.S. soldiers left after nightfall the previous evening, ending two decades of war that began as retaliation for the Sept. 11, 2001, terrorist attacks by Al Qaeda, the terrorist group based in Afghanistan.

The Taliban, the fundamentalist group that U.S. forces drove from power only to see it regain control of the country in recent weeks, celebrated the American withdrawal by firing weapons in the air and scavenging for abandoned equipment at Kabul’s airport.

The departure of U.S. troops marked the final stage of an evacuation that flew more than 120,000 people, mostly Afghan allies, out of the country.

Biden said his administration worked tirelessly to help Americans leave Afghanistan, adding that diplomatic efforts would continue now that military operations have ended.

Secretary of State Antony J. Blinken said Monday that U.S. diplomats would pressure the Taliban to ensure safe passage.

“Our commitment to them and to all Americans in Afghanistan and everywhere in the world continues,” he said.

Blinken said many of the remaining Americans were dual citizens with “deep roots and extended families” in Afghanistan, and they’re facing a “painful choice” about whether to leave.

Thousands of diplomats, foreign service officers and civil servants here and overseas have been dedicated to the evacuation effort in recent weeks, according to State Department officials.

Hunched over rows of computers in hidden rooms at department headquarters, a core staff has placed tens of thousands of phone calls and sent tens of thousands of emails to contact U.S. citizens and Afghan allies.