In 1954, after several years of sporadic acting in minor westerns, Reagan signed a lucrative contract to become the host of the General Electric Theater , a new television drama series. Reagan introduced each show and acted in some of them. He also became active in GE corporate relations, touring the company's plants and serving as its "goodwill ambassador" to the public. He spent much time in the company of Earl Dunckel, who handled public relations for the GE Theater and who bombarded Reagan constantly with his deeply conservative political views.

Similar views began to appear more and more often in the increasingly frequent and increasingly political speeches Reagan gave for General Electric in the mid- and late 1950s, when he became not just the host of the company's television series but, in effect, its most prominent corporate spokesman. His subject was almost invariably the wastefulness and intrusiveness of government (which should, he insisted, "be reduced to the barest minimum") and the bankruptcy of the "welfare state." In public, at least, nothing remained of his earlier liberal enthusiasms and his fervent support of the New Deal.

In late 1959, Reagan reluctantly accepted an invitation from the Screen Actors Guild to return as president; he steered the union through a bitter and ultimately unsuccessful strike in which SAG members demanded a share of the profits the studios were receiving for selling film rights to television. But Reagan's main interests now lay elsewhere, and shortly after the unhappy end of the strike he resigned as both president and board member of SAG and never again took an active role in the organization. Instead, he plunged into Republican politics. Although he was still nominally a Democrat, he worked for Richard Nixon in the 1960 presidential campaign (and in 1962 officially changed his party affiliation). But his own politics were, in fact, well to Nixon's right. His fiery speeches for GE in early 1961 and 1962 were fervently anti-Communist and expressed the unhappiness of the party's right wing with the bipartisan commitment to "containment" that had shaped American foreign policy since 1948. Reagan, like the right's great hero of the early 1960s, Barry Goldwater, spoke of the need for "victory" in the battle against Communism.

In 1962, the Kennedy administration launched an antitrust investigation of MCA, one of Hollywood's most powerful talent agencies, which in the 1950s used heavy and some believed illegal pressure to drive competitors out of business and establish a virtual monopoly over large segments of the film industry. Reagan was president of the Screen Actors Guild during the period of MCA's most rapid and ruthless expansion; his own agent was a power in the company; and there were charges that Reagan had used his influence with SAG to help MCA's rise to dominance. The justice Department subpoenaed Reagan's tax returns, and rumors of improper behavior that had begun in 1960 grew to new levels. At about the same time, General Electric canceled the GE Theater, and Reagan was suddenly without employment.

But Reagan's problems did not last long. In September, MCA reached an agreement with the Justice Department to divest itself of some of its divisions; the government then dropped its investigation of Reagan. In the meantime, Reagan found a new role as the host and narrator of Death Valley Days , a television western sponsored by Borax. And he accelerated his political activities, speaking now not as a corporate spokesman but as an independent political figure much in demand by the large and growing Republican right wing.

By 1964, Reagan had been socially friendly for more than a decade with Barry Goldwater, who ran for and won the Republican presidential nomination. Reagan eagerly agreed to help Goldwater's campaign. One week before the election, at Goldwater's request, Reagan appeared on national television and gave a memorable speech, "A Time for Choosing," in which he presented the conservative views on major issues he had been promoting in California for years. "You and I have a rendezvous with destiny," he grandiloquently concluded, in a phrase associated with his boyhood idol Franklin Roosevelt. "We can preserve for our children this last best hope of man on earth or we can sentence them to take the first step into a thousand years of darkness. If we fail, at least let our children, and our children's children, say of us we justified our brief moment here. We did all that could be done." The speech created a political sensation. David S. Broder of the Washington Post called it "the most successful political debut since Willam Jennings Bryan electrified the 1896 Democratic convention with his 'Cross of Gold' speech." Almost overnight, Reagan became a national political figure—a hero to those on the right who even before the election were losing faith in Goldwater. After the shattering Republican defeat that fall, the party's conservative wing began looking to Reagan for leadership.