Daniel Ellsberg, who exposed U.S. failures in Vietnam in Pentagon Papers, dies at 92

June 16 (UPI) -- Daniel Ellsberg, the military analyst who famously leaked the trove of Vietnam War documents known as the Pentagon Papers, died on Friday at his home in California. He was 92.

Ellsberg had sent an email to his friends and supporters in March saying that he had inoperable pancreatic cancer and that doctors had given him three to six months to live.

Ellsberg was born on April 7, 1931, in Chicago. He grew up in Michigan and joined the Marines in 1954. He extended his enlistment to ship out with his battalion to the Middle East for the Suez crisis in 1956.

After earning a doctorate from Harvard, he joined the RAND corporation, where he studied game theory involving crisis situations and nuclear warfare.

In 1964, Ellsberg became an adviser to Defense Secretary Robert McNamara and helped consult on America's escalating involvement in Vietnam. In 1967, McNamara commissioned the Vietnam Study Task Force to chronicle U.S. involvement in Vietnam from 1945 onward. The 47-volume report contained sensitive material exposing American policy failures, which were kept from the American public.

Ellsberg worked on the study and became convinced its analysis should be known publicly. By the late 1960s, as Ellsberg began to openly oppose the war, he and Anthony Russo Jr., a fellow colleague at RAND, began to photocopy the 47-volume Pentagon study in order to share it with others.

He first took the documents to Sen. William Fulbright, the chairman of the Foreign Relations Committee, who refused to act. Then he went to veteran New York Times journalist Neil Sheehan, who he had first met in Vietnam, providing him with 7,000 pages of classified documents revealing that the government was deceptive about U.S. prospects for victory in the war.

At first, the Nixon administration obtained an injunction against the publication of the report, saying national security was at stake.

The issue was taken to the Supreme Court, which on June 30, 1971, ruled 6-3 in favor of allowing The New York Times and The Washington Post to publish their stories. The case reinforced a standard that the press should not be censored from publishing something, unless there's a national emergency.

Ellsberg's anti-war activism continued throughout the rest of his life. In an effort to stop the Iraq war, he called on government officials to leak documents to Congress and the press showing that the Bush administration was lying in building its case against Saddam Hussein.

"Don't wait until the bombs start falling," Ellsberg said in 2003. "If you know the public is being lied to and you have documents to prove it, go to Congress and go to the press."

Ellsberg also reflected on his actions during the Vietnam War, saying that he should have disclosed the Pentagon Papers earlier.

"Do what I wish I had done before the bombs started falling" in Vietnam, Ellsberg said. "I think there is some chance that the truth could avert war."