Tom Bowman

Colin Powell became a household name because of the four stars on his Army uniform and his iconic statements about Iraq.

In the first Iraq war in 1991, he famously described what the U.S. would do to the Iraqi army that had invaded neighboring Kuwait: "We're going to cut it off, and then we're going to kill it."

Such chilling bravado — and the subsequent victory over Iraqi leader Saddam Hussein — made him one of the most formidable and admired public figures.

The Dulles Expo Center outside Washington, D.C., is usually reserved for home and garden or gun shows. Now the cavernous center hosts thousands of Afghan refugees. It's wall to wall with cots and now includes a medical center and cafeteria — serving halal food — for the steady stream of people.

There are stacks of pillows and blankets, and soldiers and government workers walk through the crowd of men and women in traditional garb.

The quick collapse of the Afghan National Army stunned many, including the Pentagon's top military officer, Gen. Mark Milley. He told reporters this week that the U.S. intelligence community estimated that if U.S. forces withdrew, it would be weeks, months, even years before the Afghan military fell to the Taliban.

Instead, it was just 11 days.

So what happened? How could U.S. officials be so wrong?