An Army private charged in the largest leak of classified material in U.S. history said Thursday that he sent the material to WikiLeaks to enlighten the public about American foreign and military policy and that he didn't think it would harm the United States.

Pfc. Bradley Manning gave a detailed explanation of his actions in a military courtroom Thursday as he entered guilty pleas to some charges.

"I believed that if the general public, especially the American public, had access to the information ... this could spark a domestic debate on the role of the military and our foreign policy in general," Manning said. He said he was troubled by counterinsurgency strategies that seemed to ignore "the complex dynamics of the people living in the environment."

A judge is weighing whether to accept Manning's guilty plea to reduced charges on 10 counts, which carry a maximum sentence of 20 years in prison. But even if the plea is accepted, prosecutors can still pursue a court-martial on the remaining 12 charges. One of those is aiding the enemy, which carries a possible life sentence.

Manning, a 25-year-old Oklahoma native, admitted Thursday that he sent hundreds of thousands of Iraq and Afghanistan battlefield reports, State Department diplomatic cables, other classified records and two battlefield video clips to WikiLeaks in 2009 and 2010 while working as an intelligence analyst in Baghdad.

The slight, bespectacled soldier read from a 35-page statement for more than an hour, speaking quickly and evenly, with little emotion, even as he described how troubled he was by the material he leaked.

The battlefield reports were the first documents that Manning decided to leak. He said he opted to send them to the anti-secrecy website after his efforts to give them to The Washington Post and The New York Times were rebuffed.

Manning said that, in his experiences, the battlefield reports were not treated as especially sensitive, particularly after the events they documented faded into the past.

He said he was concerned about leaking hundreds of thousands of sensitive State Department cables but that he ultimately decided they would not be harmful since they were so widely distributed within the military.

"I thought these cables were a prime example of the need for a more open diplomacy," Manning said. "I believed that these cables would not damage the United States. However, I believed these cables would be embarrassing."

Manning said when he was on leave, he visited his boyfriend in the Boston area and said he asked him hypothetical questions about how to go about sharing the information he had. He said his boyfriend didn't really understand what he was talking about and that their relationship grew distant.

Manning said at this point he was disillusioned by the war in Iraq and his personal life and decided to share his information with the press. He said he first called The Washington Post but didn't think the reporter took him seriously.

Manning said he then called The New York Times' tipline but never received a reply. He considered sending the information to Washington news outlet Politico but said he did not due to weather conditions at the time.

The Obama administration has said releasing the information threatened valuable military and diplomatic sources and strained America's relations with other governments. The administration has aggressively pursued individuals accused of leaking classified material, and Manning's is the highest-profile case.

Manning's statements before the hushed courtroom dovetailed with the position taken by his supporters around the world - that leaking the documents was an act of conscience. Manning has been embraced by some left-leaning activists as a whistleblowing hero whose actions exposed war crimes and helped trigger the Middle Eastern pro-democracy uprisings known as the Arab Spring in 2010.

Manning said he was appalled by a combat video that showed an aerial assault that killed two employees of the Reuters news organization.

"The most alarming aspect of the video to me was the seemingly delightful bloodlust the aerial weapons team happened to have," Manning said, adding that the soldiers' actions "seemed similar to a child torturing ants with a magnifying glass."

WikiLeaks did not immediately return a text message seeking comment on Manning's statement. The group has always been careful never to confirm or deny whether Manning was the source of its cache of leaked U.S. documents, and the secret-spilling site didn't deviate from that approach Thursday.

On its Twitter feed, WikiLeaks called Bradley Manning an "alleged source" and noted that he was detailing "what he says" were his interactions with the online organization.

But WikiLeaks made no secret of its admiration for what Manning said was his decision to expose the documents to the world. A message posted to Twitter by the Manning supporter Nathan Fuller and retweeted by WikiLeaks said:

Bradley Manning pleaded not guilty to aiding the enemy. Aiding the public is not aiding the enemy. #FreeBrad #WikiLeaks