IF THE ALLEGATIONS are true, Pfc. Bradley Manning facilitated a damaging breach of national security by funneling thousands of classified documents to the rogue Web site WikiLeaks. But even if so, Mr. Manning does not appear to deserve the treatment he has been receiving at the military brig in Quantico, Va.

Mr. Manning, who could face life behind bars if convicted, has been held in maximum security at the Virginia facility since July. He spends 23 hours a day in his cell. He is allowed out for one hour of exercise each day, has periodic television and visitation privileges and access to reading material, but he is forced to take meals alone and is not permitted direct contact with the others on the cellblock, although he may speak with them through the bars.

For three days in January, Mr. Manning was classified as a “suicide risk,” which meant he had to stay in his cell for 24 hours a day, stripped to his underwear and in “essential blindness” because his glasses were taken away. For roughly the first week of March, he was forced to sleep naked, with only a blanket. Yet brig psychologists and psychiatrists consistently concluded that Mr. Manning was not a danger to himself. (Mr. Manning has since been given a “smock” to wear to bed; he is clothed in a standard jumpsuit during the day, according to the Pentagon.) Mr. Manning is asking the brig’s commander to move him to medium security, which would allow him access to communal areas.

Senior Defense Department officials say the current level of security is appropriate because of the seriousness of the charges against Mr. Manning. And they argue that they have imposed additional, “prevention of injury” (POI) restrictions to keep Mr. Manning from hurting himself — or from being hurt by others.

Some at the Defense Department may feel pressured to exercise all precautions to prevent harm from befalling Mr. Manning; after all, they would undoubtedly be blamed for either allowing or causing such harm. But it is difficult to understand why Mr. Manning is being held under these extremely restrictive conditions. His alleged crimes are serious, but they are not violent. The brig at Quantico is tiny, holding roughly one dozen individuals at any given time; shouldn’t personnel be able to control such a population even if some wish to harm a man they may consider a traitor?

The episodes of forced nudity are particularly disturbing. In both instances, nudity was imposed after, according to Mr. Manning, he had run-ins with brig personnel, leading to questions about whether it was payback for mouthing off. And Mr. Manning’s treatment comes uncomfortably close to the kind of intimidating and humiliating tactics disavowed after the abuses at the Abu Ghraib and Guantanamo prisons that eroded the country’s standing in the world.

Before abruptly resigning his post this week, State Department spokesman P.J. Crowley called Mr. Manning’s treatment “ridiculous and counterproductive and stupid.” That sounds about right.