What should have been done about a mentally unstable young man who tried to set off a car bomb in the Loop to kill “at least a hundred people”?

Americans will never be of one mind as to what should have been the prison sentence for Adel Daoud, now 23, who was caught in an FBI anti-terrorism sting when he was 18. But we’d have to say that U.S. District Judge Sharon Johnson Coleman got it about right.

Judge Coleman sentenced Daoud to 16 years, a punishment that reflects the serious nature of his crimes — and the need to deter other would-be terrorists — while recognizing that he was an immature and emotional mess.

Federal prosecutors called for a sentence of 40 years. We appreciate the logic of that, given that Daoud not only pushed the button on what he thought was a massive bomb, but also plotted to have an undercover agent killed and stabbed another inmate.

Daoud’s defense attorney, Thomas Anthony Durkin, called for little or no prison time, arguing that what his client needed most was better mental health treatment and medication. Daoud, he said, was an “impressionable teenager” — and that he was.

Daoud, who eventually pleaded guilty, had to undergo months of treatment just to be deemed fit to stand trial.

But how could Daoud be allowed to walk? How wise would such leniency look if he had set off a real bomb? Daoud was naive, but also a willing plotter. As he said to the undercover agent who warned him that “people are gonna die” if he pressed the detonator, “Yeah, that’s the point.”

Daoud caught a break. He could be freed in less than 10 years.

It “gives him a life,” Durkin conceded. “We can’t ask for anything more than that.”

Exactly right.

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