SAN DIEGO -- A former decorated swift-boat captain in the Vietnam War, who went on to become an official at the Pentagon, was sentenced Monday in San Diego to 37 months behind bars for keeping hundreds of child pornography images on his computers.

Wade Sanders, 69, will surrender in July to begin serving the federal prison term handed down by U.S. District Judge Thomas Whelan.

Sanders told the judge that he pleaded guilty to possession of child pornography because that's what he did. Sanders had faced a maximum of 10 years in prison.

The case against Sanders began in 2007 when FBI agents went online to look for people using sites to share child porn.

Three computers seized in a raid at Sanders' San Diego home had child porn on them, prosecutors said.

Defense attorney Knut Johnson said Sanders apologized and took full responsibility for his actions.

The defendant is most upset about disappointing his family, friends and supporters, his attorney said.

"He was obsessed with the topic (of child porn)," Johnson said outside court. "He was writing an article about it. He took notes about it. And it was just the wrong topic to get obsessed about."

Sanders was awarded the Bronze Star, Silver Star and Purple Heart for his service in Vietnam. He served as Deputy Assistant Secretary of the Navy during the Clinton administration.

In 2004, Sanders stood behind fellow veteran John Kerry as the Massachusetts senator accepted the Democratic Party's nomination for president.

In a letter to the court, Kerry urged the judge to consider Sanders' service to his country and community work while fashioning a fair sentence.