The reason most people in America don't worry about polio, smallpox, measles, mumps, or rebella today is because of vaccines.

The threat of the Delta virus remains real.

But we are prepared.

We have the tools.

We can do this.

That was President Biden, tripling down on vaccines, pushing for a third shot to protect Americans from COVID-19.

We're going to be talking to the U.S. Surgeon General just ahead.

Good morning and welcome to morning, Joe.

It's Thursday, August 19th.

Mika has the morning off.

Willie, a lot in the news as usual.

Absolutely. And in addition to COVID-19, President Biden is reiterating his defense of his decision to withdraw American troops from Afghanistan.

In a new interview with ABC News, the president argues some of the chaos we've seen was inevitable, adding troops will stay in Afghanistan until all

American civilians are out of the country. We've got a pair of reports first from NBC's Kelly O'Donnell

and then from NBC's Richard Engel in Kabul.

A chilling assessment. The U.S. military does not have sufficient forces to rescue Americans who cannot get to

the Kabul airport evacuation point. We don't have the capability to go out and collect up large

numbers of people. The U.S. is relying on the Taliban to let Americans and Afghan allies pass through

checkpoints to reach the airport.

A risky journey.

In an interview with ABC News, President Biden said he knew chaos was inevitable.

We're going to go back in hindsight and look, but the idea that somehow there's a way

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