The real tragedy of the Omar Khadr trial.

When Attorney General Eric Holder announced last fall that he planned to try Khalid Sheikh Mohammed in a civilian court in New York, he was met with a firestorm of abuse. Despite the fact that hundreds of terror suspects have been tried and convicted in U.S. courts, the administration's Republican opponents spun out a thousand reasons for treating Mohammed differently: His trial would create a target in New York City that would cost millions of dollars for security measures; he would use the proceedings to spread jihadist propaganda; he shouldn't be entitled to the constitutional rights and protections afforded U.S. citizens. In short, KSM became the poster boy for the man too dangerous for the law. In March, the White House indicated that a decision on Mohammed's trial was just weeks away. Months later, the administration is still mulling.

But instead of subjecting the so-called "worst of the worst" to a military tribunal, this past week the Obama administration fired up the tribunal system to try Omar Khadr, a child soldier. Khadr's defense counsel, Jon Jackson, collapsed Thursday while questioning a witness and was airlifted back to the United States for treatment. There will be at least a 30-day delay in the proceedings. Maybe we can use this small break to look again at what Guantanamo has become and to acknowledge that Omar Khadr represents everything we shouldn't be trying before a secretive military commission.

At 23, Khadr is the youngest detainee of the 176 remaining prisoners at Guantanamo Bay. He's been there for eight years—one-third of his life. Born in Toronto, he is the only Westerner there. Khadr is charged with being an "unlawful enemy combatant" (later changed to "unprivileged enemy belligerent") for allegedly throwing the grenade that killed Special Forces Sgt. Christopher Speer in Afghanistan in July 2002. Khadr was 15 at the time.

As a U.N. envoy who condemned the trial this week noted, no child has been prosecuted for a war crime since World War II. Under international law, children captured in combat are to be treated as victims, not soldiers, and their captors are meant to rehabilitate and repatriate them. There's also a question as to why someone who allegedly committed acts of war against a military invader has been classified as a war criminal and terrorist. Finally, there's the question of physical abuse: Khadr's attorneys say the prosecutors have relied on confessions extracted after Khadr was coerced, abused, and threatened with gang rape by military interrogators. Last week, the military judge in the case ruled that Khadr's statements were admissible, and they make up the bulk of the evidence against him.

In short, Khadr's trial forces us to revisit the long and disappointing history of President Bush's military commissions, the demands of international law, the terrible abuse of prisoners held by the United States—everything we want to forget about our worst legal missteps in the wake of 9/11.

Nobody disputes that there should be consequences for a teenager who throws a grenade on a battlefield. The question is whether a lifetime in prison, after a third of a lifetime at Gitmo, is proper, and whether the procedures that have been set up at Gitmo are fair: child soldier, torture, plus eight years of justice delayed. It's why ACLU staff attorney Ben Wizner describes the case as "the perfect storm of what's wrong with the military commission system."