"Chelsea Manning is somebody who went through the military criminal justice process,was exposed to due process,was found guilty,was sentenced for her crimes,and she acknowledged wrongdoing,"he said.

"Mr Snowden fled into the arms of an adversary,and has sought refuge in a country that most recently made a concerted effort to undermine confidence in our democracy."

He also noted that,while the documents Manning provided to WikiLeaks were"damaging to national security",the ones Mr Snowden disclosed were"far more serious and far more dangerous". (None of the documents Manning disclosed were classified above the merely"secret"level.)

Manning was known as Bradley Manning when she deployed with her unit to Iraq in late 2009. There,she worked as a low-level intelligence analyst helping her unit assess insurgent activity in the area it was patrolling,a role that gave her access to a classified computer network.

She copied hundreds of thousands of military incident logs from the Afghanistan and Iraq wars,which,among other things,exposedabuses of detainees by Iraqi military officers working with American forces and showed thatcivilian deaths in the Iraq war were probably much higher than official estimates.

The files she copied included about 250,000 diplomatic cables from American embassies around the world showing sensitive deals and conversations,dossiers detailing intelligence assessments of Guantanamo detainees held without trial,and a video ofan American helicopter attackin Baghdad in which two Reuters journalists,among others,were killed.

She decided to make all these files public,as shewrote at the time,in the hope that they would incite"worldwide discussion,debates,and reforms".

WikiLeaks disclosed them - working with traditional news organisations includingThe New York Times- bringing notoriety to the group and its founder,Julian Assange.

The disclosures set off a frantic scramble as Obama administration officials sought to minimise any potential harm,including getting to safety some foreigners in dangerous countries who were identified as having helped American troops or diplomats. However,prosecutors presented no evidence that anyone was killed because of the leaks.

At her court-martial,Manning confessed in detail to her actions and apologised,saying she did not intend to put anyone at risk and noting that she was"dealing with a lot of issues"at the time she made her decision.

Testimony at the trial showed that she had been in a mental and emotional crisis as she came to grips,amid the stress of a war zone,with the fact that she was not merely gay but had gender dysphoria. She had been behaving erratically,including having angry outbursts and lapsing into catatonia mid-sentence. At one point she had emailed a photograph of herself in a woman's wig to her supervisor.

Prosecutors said that,by making secret material available for publication on the internet,anyone - including al-Qaeda - could read it. And they accused Manning of treason,charging her with multiple counts of the Espionage Act as well as with"aiding the enemy",a potential capital offence,although they said they would not seek her execution.

Manning confessed and pleaded guilty to a lesser version of those charges without any deal to cap her sentence. But prosecutors pressed forward with a trial and won convictions on the more serious versions of those charges. A military judge acquitted her of"aiding the enemy".

In her commutation application,Manning said she had not imagined that she would be sentenced to the"extreme"term of 35 years,a term for which there was"no historical precedent". (There have only been a handful of leak cases,and most sentences are in the range of one to three years.)

"I take full and complete responsibility for my decision to disclose these materials to the public,"she wrote."I have never made any excuses for what I did. I pleaded guilty without the protection of a plea agreement because I believed the military justice system would understand my motivation for the disclosure and sentence me fairly. I was wrong."

After her sentencing,Manning announced that she was transgender and changed her name to Chelsea.

The military,under pressure from a lawsuit filed on her behalf by Chase Strangio of the American Civil Liberties Union,has permitted her to transition partly to life as a woman,including giving her cross-sex hormones and letting her wear female undergarments and light cosmetics.

But it has not let her grow her hair longer than male military standards,citing security risks,and Manning said she had yet to be permitted to see a surgeon about the possibility of sex reassignment surgery.

Until recently,the military discharged transgender soldiers. In June,Secretary of Defence Ashton Carter changed that policy and said it would instead provide treatment for them,eventually including such surgery if doctors said it was necessary.

But President-elect Donald Trump mocked that change as excessively"politically correct",raising the possibility that he will rescind it.

Even if he does,Manning will soon no longer be subject to the military's control.

The New York Times