During his sentencing hearing following his conviction at a court martial for the country's biggest breach of classified data, Captain Joe Morrow told the hearing in Fort Meade, Maryland: "He betrayed the United States. For that betrayal he deserves to spend the majority of his remaining life in prison."
The 25-year-old private was found guilty of 20 criminal counts tied to the leaking of more than 700,000 classified files, videos and diplomatic cables. He faces the possibility of a maximum 90 years in prison.
Manning's defence lawyers have said he was naive but well-intentioned in handing over documents to the pro-transparency website. He was found not guilty of the most serious charge, aiding the enemy, which carried the possibility of life in prison without parole.
Manning was assigned to Iraq in 2010 when he handed over the files. He has apologised to the court and said he understood that he "must pay a price." Sentencing is due either this week or next.