FORT MEADE, Md. – Bradley Manning purposely joined the Army and deployed to Iraq to use his extensive computer skills to disclose protected U.S. secrets that he knew would assist terrorist organizations in their efforts to attack the United States, the chief prosecutor in Manning’s military court martial said Thursday.

“WikiLeaks was merely the platform that Pfc. Manning used to make sure all the information was available to the world, including the enemies of the United States,” Army Maj. Ashden Fein said in his closing argument near the end of Manning’s trial. “Pfc. Manning deliberately disclosed compromised information to the world.”

Fein recounted in detail the heart of the government’s case: that Manning sought out WikiLeaks as his vehicle for exposing more than 700,000 combat videos, terrorist detainee assessments, State Department cables and other secret material.

“He was not a naive soldier,” Fein said.

The prosecutor told the judge, Col. Denise Lind, that Manning spent untold hours transmitting documents to WikiLeaks and hours more chatting online with WikiLeaks founder Julian Assange and following his orders, and even more time “wiping” his computer clean, thinking he could “hide his tracks.”

Many times late at night, Fein said, Manning sat alone in his unit’s intelligence gathering hut southeast of Baghdad, with no fellow soldier sitting to his right or left as was normal, bending over the glow of his computer screen and thrilling at the prospect of his coming celebrity.

On the wall in the Fort Meade courtroom, Fein displayed a photograph the soldier took of himself, appearing “gleeful and grinning” after sending his first links to WikiLeaks. He signed the transmission, “Have a Good Day.”

“The only human Pfc. Manning ever cared about was himself,” Fein said. “He was interested in making a name for himself. The flag meant nothing to him.”

The trial, which began June, is nearing an end. Lind will decide whether Manning was a whistle-blower who sought to enlighten the world about government misconduct, especially in Iraq and Afghanistan, or a traitor whose betrayal of the United States merits a sentence of life in prison.

The prosecution stressed that the 25-year-old from a small Oklahoma town committed espionage, endangered this country’s national security and aided organizations like al-Qaida that continue to plot terrorist strikes against the U.S.

Defense lawyers say Manning was merely an ideological soldier upset with the horrors of war who wanted to alert the public through journalistic channels that Washington has been misleading them. Their closing argument is to come today.