Trump Jr.’s admission he turned to Russians for help: Has anything like this happened before?

There is only one known historical parallel to the Trump campaign’s contacts with the Russians, and it involves Richard M. Nixon. Running for president in 1968, Nixon told H. R. Haldeman, his eventual White House chief of staff, to “monkey wrench” peace talks in Vietnam in order to scuttle any deal that would have handed Hubert Humphrey, the Democratic nominee, a political victory in the closing days of the election.

Nixon, a former senator and vice president, had a relationship with the South Vietnamese government. Earlier in the year, he had met with the country’s ambassador and brought along Anna Chennault, a prominent Chinese-American Republican. As the author John A. Farrell writes in his new book, “Richard Nixon: The Life,” which reports the “monkey wrench” instructions, the call between Nixon and Haldeman took place on Oct. 22, 1968, and Haldeman dutifully jotted down what he was told.

A group of aides to Ronald Reagan did meet in the fall of 1980 with an individual claiming to be an emissary from the Iranian government, but that person’s legitimacy was never determined.

Moscow has, however, tried to meddle in previous American elections. The historian Michael R. Beschloss recounts in “The Crisis Years: Kennedy and Khrushchev, 1960-1963,” an account of the relationship between the United States and the Soviet Union during the Kennedy presidency, that the Soviet ambassador in Washington secretly reached out to both John F. Kennedy and Adlai Stevenson, another Democratic presidential hopeful, during the 1960 campaign. The ambassador was rebuffed by both candidates.