Did Blumenthal join the Marine Reserves to avoid being deployed?

At one point in the interview, Mr. Blumenthal, a Democrat, said he joined the Marine Corps Reserve in April 1970 knowing that reservists could be activated for service in Vietnam. “I did not want to avoid service,” he said. “I did realize reservists could be called up, and that it was something that I wanted to do.”

But military experts said there was no expectation that reserve units would be activated at the time Mr. Blumenthal enlisted, particularly given how drastically public opinion had turned against the war.

In fact, President Richard M. Nixon had begun in 1969 to reduce the American troop presence in Vietnam and transfer more responsibility for fighting to the South Vietnamese, said James E. Westheider, a history professor at the Clermont College campus of the University of Cincinnati who has written about Vietnam.

“By the time he was in the service, if he was in the Marine Reserves, he was not going to Vietnam,” Mr. Westheider said.