U.S. Army Private Bradley Manning has pleaded Guilty to sending diplomatic cables and other secret documents to WikiLeaks.  But he’s denying the most serious charge of aiding the enemy.

25-year-old Manning testified before a military tribunal, detailing what he calls illegal and corrupt activities by Americans in the wars in Iraq and Afghanistan, and that he wanted to start a public debate.

Among the secrets that proved embarrassing for the U.S. was video taken from an Apache Helicopter in 2007 as crewmembers slaughtered a dozen civilians in an Iraqi market.  The crew claimed the civilians were “insurgents”.

Manning described other incidents that led him to believe the war was wrong.  He was flabbergasted when his superiors told him to drop an inquiry as to why Iraqi authorities were detaining civilians, only to find out the civilians’ only crime was to print critiques of the U.S.-backed regime.

Most important for WikiLeaks and its founder Julian Assange, Manning took full blame for leaking the documents, saying that the recipients put no pressure on him to obtain any data.

In fact, Manning says he reached out to WikiLeaks only after two of America’s most-respected newspapers showed no interest in his revelations.

Assange remains holed up in the Ecuadorian Embassy in London, to avoid what he calls trumped-up and U.S.-engineered sex abuse charges in Sweden.

Manning’s court-martial is scheduled to start on 3 June.