NATIONAL VIEW: The Biden team just missed a big opportunity on Guantánamo Bay

THE POINT: A plea deal for three 9/11 suspects, now scuttled, was the best available option.

The United States had an opportunity to close a chapter on a sad, decades-long saga when the government reached a plea deal with three men accused of plotting the Sept. 11, 2001, attacks. Then, within days, Defense Secretary Lloyd Austin squandered that chance.

Khalid Sheikh Mohammed, Walid bin Attash and Mustafa al-Hawsawi all agreed recently to admit their guilt before the military commission tasked with determining their fates, surrendering any chance to appeal, in exchange for the removal of the death penalty as a possible punishment. Getting to that point took 16 years. That’s counting from the initial hearing in the case (the men were in custody for five years before that), when the defendants also wanted to plead guilty but with execution still on the table. What happened instead, after they withdrew those pleas, looked worse for the United States: Justice remained unserved, and Guantánamo Bay remained open, letting the whole world look for a while longer at a symbol of this country’s hypocrisy on human rights.

Mr. Austin’s decision to revoke the plea deal is, on a gut level, understandable. The prisoners are accused of engineering the deaths of 2,977 people at the World Trade Center, at the Pentagon and in Shanksville, Pa. — some of whose families have said the terrorists deserve “no mercy.” Obviously, offenders in the United States have been and still are executed for far less. The United States killed Osama bin Laden and Ayman al-Zawahiri outright when the U.S. military found them. Yet, on closer examination, the choice is mystifying: How could the secretary of defense himself not have known about an agreement so painstakingly negotiated, over so long a period, by an official whom he tasked with overseeing the process? And how can President Joe Biden’s administration fulfill its stated objective of shutting down the prison if it can’t close cases?

It’s unlikely the government will manage to secure the death penalty for these accused terrorists — if it manages to secure any sentence at all without a plea deal. The delays that have characterized the case so far will continue to define it, largely because the military commissions created under President George W. Bush exist outside established military or civilian legal process. (That was, after all, the whole point of detaining and trying accused terrorists as unlawful combatants at Guantánamo Bay.) There was some legitimate rationale for trying unlawful combatants in unique forums. But there are few clear rules for their operation, and every question about how to conduct a trial has required extensive consideration — and expensive consideration, considering lawyers, judges and more have to fly to the naval base for each hearing. The cost, according to the New York Times, has totaled around $13 million per prisoner throughout the facility’s existence.

Imagine that a trial does start, against the odds. The testimony would probably feature extensive descriptions of the torture to which these men were subjected at CIA black sites, including confinement in coffin-size boxes and, for ringleader Khalid Sheikh Mohammed, as many as 183 instances of waterboarding. That would both remind the world of disgraceful U.S. conduct — and, crucially, render much of the evidence tainted for the purposes of securing a harsh sentence. The only way out was a plea deal. Now, the United States is right back where it started.

Only 30 inmates remain at Guantánamo Bay — the rest of the 780 brought to the base are gone, nine of them having died at the prison. The goal should be to turn 30 into zero. But that’s complicated. Nineteen prisoners sit in “law-of-war” detention, still uncharged. Sixteen of those are recommended for transfer to the custody of countries willing to accept them, a process that the administration should prioritize. Yet three are deemed too dangerous for that move. Then there are the four inmates who’ve been convicted and the seven who have been charged with their cases pending. Gitmo can’t go until these inmates, too, are gone — and getting them gone will require a law from Congress permitting their transfer to U.S. soil.

But truly concluding this era in our national life will require more: finally bringing these men to justice, and justice to these men. Plea deals like the one that collapsed recently are an orderly pathway to a procedurally legitimate outcome. Pursuing them is the correct course from a practical standpoint — just not a political one. The administration didn’t manage to do the right thing. But the president still has a chance to correct course after November’s vote, unencumbered by electoral considerations. In doing so, he would leave as his legacy the end, finally, of a grim time for his country.

The Washington Post