[5][2] He came to the attention of William F. Buckley Jr., editor of the fledgling National Review, shortly after its founding in late 1955, when he wrote an essay for the Harvard Young Republican paper, titled "Cult of Doubt."

[1][2][3] Goldwater's victory in the bitterly fought nomination contest over New York Governor Nelson A. Rockefeller and the previously dominant moderate or liberal establishment in the Republican Party was the first stage in the rise to national power of the conservative movement.

[6] In 1966, Rusher together with Max Yergan became co-chairmen of the American-African Affairs Association (AAAA), which lobbied the United States to recognize Rhodesia.

[10] Beginning in the late 1950s and continuing well past his retirement from National Review at the end of the 1980s, Rusher was a very active public speaker on college campuses and in other forums, where he defended and advocated the conservative position.

In the early 1970s, he was the main conservative representative on a PBS television debate show, The Advocates, which also featured the later governor of Massachusetts, Michael S. Dukakis, the 1988 Democratic presidential nominee.

He believed that Ronald Reagan, whom he promoted as a possible presidential candidate as early as 1967 and in whose reluctant campaign for the Republican nomination in 1968 he had some involvement, was the ideal leader for this purpose.

In terms of issues, he was heavily motivated by anti-communism throughout his career, was an outspoken opponent of the 1960s counterculture, and took a special interest in what he considered pervasive liberal bias in the news media.

In 1976, Rusher together with Marvin Liebman and a former CIA officer, David Atlee Phillips, founded a new pro-Rhodesian lobbying group, the American-Rhodesian Association, whose object was having the U.S. recognize Rhodesia.

[13] Rusher also wrote about the status of political prisoners that "about four thousand Allende sympathizers were prosecuted and convicted of specific crimes after the 1973 coup", of which all "but a dozen were sent into exile abroad or were jailed".

[14] Rusher wrote five books: Special Counsel (1968), a memoir of his time on the Internal Security Subcommittee;[2] The Making of the New Majority Party (1975), in which he advocated the establishment of a new conservative party to replace the Republicans in the post-Watergate period;[1][2][3] How to Win Arguments (1981), a primer of debating techniques; The Rise of the Right (1984), a history of the conservative movement from the 1950s to the early 1980s, re-released in 1993 with an appendix covering more recent developments;[1][2] and The Coming Battle for the Media (1988).

At times, Rusher doubted the GOP could ever be converted to true conservatism, and spent some of his career unsuccessfully trying to jump-start a conservative third party.