'I take full responsibility for decision to leave Afghanistan by August 31,' Biden tells nation

"I take full responsibility for the decision to leave Afghanistan by August 31," Biden said while addressing the nation since the US completed its military withdrawal from the country

He said choice in Afghanistan was between leaving or escalating the war. “That was the choice: between leaving or escalating. I was not going to extend this forever war, and I was not extending a forever exit,” Biden said.

The US president said the decision to end the US role in Afghanistan was also about ending an era of military operations aimed at rebuilding other countries.

Ending the last military intervention to arise from the 9/11 attacks was one of Joe Biden's biggest campaign promises coming into office, and the idea was overwhelmingly popular.

Following more than 2,400 US military deaths, thousands wounded and an estimated $2.3 trillion spent on an endeavour that began in victory over the Taliban only to end with those same insurgents sweeping back to power, Americans had lost interest in remaining entrenched in a “forever war” in Afghanistan.

The departure on Monday culminated in a solitary airplane lifting off at one minute to midnight local time in Kabul with the last troops and diplomats being brought home.

After two weeks of air lifts that saw more than 120,000 people – most of them Afghan allies – evacuated, the Pentagon made the final announcement that US military operations had ended late on Monday.

But the titanic effort was marred by an August 26 suicide bombing that killed more than 160 Afghans and 13 US service members.

Biden has stern words Tuesday for the group behind the bombing, Isis-Khorasan.

"We all maintain the fight against terrorism in Afghanistan and other countries," Biden said.

-- Additional input from AFP