The news from Kabul, Afghanistan just keeps getting worse.

On Thursday a bombing outside Kabul's commercial airport killed an estimated 185 people, according to reporting by the New York Times. Among the casualties were 13 U.S. service members assigned to provide security as the evacuation of U.S. citizens and Afghanis — who had assisted our military and diplomatic efforts — continued.

Reportedly, more than 200 people were wounded, including 15 U.S. military personnel. An ISIS splinter group operating in Afghanistan is believed responsible. Intelligence officials had warned in advance that there was a credible threat of such an attack.

President Biden vowed revenge. "We will not forgive. We will not forget. We will hunt you down and make you pay."

That is probably little solace to the families of the dead, including the families of the American soldiers who must live with the reality that their loved ones were among the last casualties of this long war. It is also questionable how realistic is the president's vow, given the American retreat from Afghanistan.

Editorially, we fell into the policy camp that the United States, in cooperation with allies, should have walked away from the surrender accord negotiated by the Trump administration with the Taliban and instead kept a contingent of several thousand military personnel in Kabul, operating out of the Bagram Airbase. A small force may have discouraged the Taliban from trying to seize the central government for fear of inviting a greater U.S. response. It would have been a stalemate, but one that could have protected the progress made for women, at least in the urban area. Diplomats would have had time to keep pushing for a more equitable power-sharing arrangement that preserved an Afghan government.

But having opted to continue the retreat, it was the responsibility of Biden and his generals to do it right. They have failed, spectacularly.

The only option left is to make the best of a bad situation. On Thursday, despite the bombing, 12,500 people were evacuated from Afghanistan, bringing the total airlifted abroad since Aug. 14 to about 105,000, the White House reported Friday. Biden should be prepared to abandon his Aug. 31 deadline for the end of the operation if there are U.S. citizens and endangered Afghanis still awaiting escape.

Not all who assisted the U.S. will get out. Many, and their families, will likely face a terrible fate at the hands of the Taliban. And the bombing Thursday reminds us of the potential for international terrorism to fester in a Taliban-controlled Afghanistan, the very reason the U.S. and its allies invaded the country to begin with.

As noted in an earlier editorial, Congress must eventually get at the bottom of what went so very wrong.

Intelligence assessments had estimated that Afghan forces could hold off the Taliban for one or two years, meaning any collapse of Kabul would come long after U.S. forces had left. Instead, Afghan forces abandoned their posts and Kabul rapidly fell. What is behind this epic intelligence failure?

Why did the military abandon Bagram Airbase in early July? Thirty miles north of Kabul, it could have played a major role in a pre-troop withdrawal airlift. Unlike the commercial airport, it was a military airstrip designed to be secured. It would seem that it should have kept operating until the last plane left.

Connecticut Sen. Chris Murphy, a Democrat and chairman of the Senate Foreign Relations Committee subcommittee that includes Afghanistan and counterterrorism among its responsibilities, has agreed an investigation is necessary — from the start of the Afghan campaign to its inglorious finish. That is as unrealistic and politically self-serving as arguments from Republicans that the investigation into the attack on the U.S. Capitol on Jan. 6 should be expanded to include Black Lives Matter protests and associated street riots.

Volumes have and will be written about the approach and missteps of the war in Afghanistan, but any coming congressional investigation must focus on why the retreat was so badly botched and what lessons need to be learned.

In an Aug. 19 interview, Biden suggested this outcome was inevitable.

"The idea that somehow there's a way to have gotten out without chaos ensuing, I don't know how that happens. I don't know how that happens," Biden said.

That's not good enough, Mr. President. Congress needs to find out how a less chaotic and deadly retreat could have happened and why, instead, we got this.

The Day editorial board meets with political, business and community leaders to formulate editorial viewpoints. It is composed of President and Publisher Timothy Dwyer, Executive Editor Izaskun E. Larraneta, Owen Poole, copy editor, and Lisa McGinley, retired deputy managing editor. The board operates independently from The Day newsroom.