President Obama tells us that he's asked the Pentagon whether the conditions of confinement of Bradley Manning, the soldier charged with leaking state secrets, "are appropriate and are meeting our basic standards. They assure me that they are."

If Obama believes that, he'll believe anything. I would hope he would know better than to ask the perpetrators whether they've been behaving appropriately. I can just hear President Nixon saying to a press conference the same thing: "I was assured by the the White House Plumbers that their burglary of the office of Daniel Ellsberg's doctor in Los Angeles was appropriate and met basic standards."

When that criminal behaviour ordered from the Oval Office came out, Nixon faced impeachment and had to resign. Well, times have changed. But if President Obama really doesn't yet know the actual conditions of Manning's detention – if he really believes, as he's said, that "some of this [nudity, isolation, harassment, sleep-deprivation] has to do with Private Manning's wellbeing", despite the contrary judgments of the prison psychologist – then he's being lied to, and he needs to get a grip on his administration.

If he does know, and agrees that it's appropriate or even legal, that doesn't speak well for his memory of the courses he taught on constitutional law.

The president refused to comment on PJ Crowley's statement that the treatment of Manning is "ridiculous, counterproductive and stupid". Those words are true enough as far as they go – which is probably about as far as a state department spokesperson can allow himself to go in condemning actions of the defence department. But at least two other words are called for: abusive and illegal.

Crowley was responding to a question about the "torturing" of an American citizen, and, creditably, he didn't rebut that description. Prolonged isolation, sleep deprivation, nudity – that's right out of the manual of the CIA for "enhanced interrogation". We've seen it applied in Guantánamo and Abu Ghraib. It's what the CIA calls "no-touch torture", and its purpose there, as in this case, is very clear: to demoralise someone to the point of offering a desired confession. That's what they are after, I suspect, with Manning. They don't care if the confession is true or false, so long as it implicates WikiLeaks in a way that will help them prosecute Julian Assange.

That's just my guess, as to their motives. But it does not affect the illegality of the behaviour. If I'm right, it's likely that such harsh treatment wasn't ordered at the level of a warrant officer or the brig commander. The fact that they have continued to inflict such suffering on the prisoner despite weeks of complaint from his defence counsel, harsh publicity and condemnation from organisations such as Amnesty International, suggests to me that it might have come from high levels of the defence department or the justice department, if not from the White House itself.

It's no coincidence that it's someone from the state department who has gone off-message to speak out about this. When a branch of the US government makes a mockery of our pretensions to honour the rule of law, specifically our obligation not to use torture, the state department bears the brunt of that, as it affects our standing in the world.

The fact that Manning's abusive mistreatment is going on at Quantico – where I spent nine months as a Marine officer in basic school – and that Marines are lying about it, makes me feel ashamed for the Corps. Just three years as an infantry officer was more than enough time for me to know that what is going on there is illegal behaviour that must be stopped and disciplined.