Daniel Ellsberg, the US military analyst whose change of heart on the Vietnam War led him to leak the classified "Pentagon Papers," died on Friday at the age of 92, his family said in a statement.
Ellsberg, who had been diagnosed with inoperable pancreatic cancer in February, died at his home in Kensington, California, the family said.
Long before Edward Snowden and Wikileaks were revealing government secrets in the name of transparency, Ellsberg let Americans know that their government was capable of misleading and even lying to them.
In his later years Ellsberg would become an advocate for whistleblowers and leakers and his "Pentagon Papers" leak was portrayed in the 2017 movie "The Post."
In his later years, Ellsberg, who was born April 7, 1931 in Chicago, Illinois, became a writer and lecturer in the campaign for government transparency and against the proliferation of nuclear weapons.
He said Snowden, a contractor for the National Security Agency who gave journalists thousands of classified documents on government information-gathering before fleeing the country, had done nothing wrong. He also said he considered Army Private Chelsea Manning a hero for turning over a trove of government files to WikiLeaks.
His books include "The Doomsday Machine: Confessions of a Nuclear War Planner" in 2017 and "Secrets: A Memoir of Vietnam and the Pentagon Papers" in 2002.