Exactly 50 years ago on Jan. 23, 1968, in the midst of the Vietnam War, the American naval intelligence ship USS Pueblo was hijacked in international waters by North Korea. Its crew was imprisoned and tortured. Democratic President Lyndon Johnson's lack of public response indicated American impotence and indecision.

Many aspects of that saga have been told by historians and are being commemorated today, especially because of the continued threats by North Korea to incinerate American and allied cities via nuclear-tipped intercontinental ballistic missiles.

The United States relies, in large part, on the antimissile defense shield first advocated in 1968 by Ronald Reagan when he first ran for president, although his formal proposal (the Strategic Defense Initiative, SDI) would occur some 15 years later during his first term in office.

Few Americans know that during that first 1968 campaign, Reagan spoke out many times about virtually all aspects of foreign affairs. Staunch anticommunist Reagan was the only major 1968 candidate who wanted to win the Vietnam War, and Reagan saw the hijacking of the USS Pueblo as yet another thrust of global communism which needed to be defeated.

Reagan had no illusions about the cruelty of communist North Korea. In a little-remembered film from the early 1950s, "Prisoner of War," actor Reagan portrayed an American army captain during the Korean War who is sent on a secret mission to learn about how American prisoners of war are being mistreated. He is shocked to see beatings, starvation, and torture. Reagan said at the time, "Every torture scene and incident was based on actual happenings documented in official Army records."

During the spring of 1968, the continued captivity of the USS Pueblo crew made headlines just as the presidential election was heating up as well. Anti-war Sen. Eugene McCarthy's strong showing in the New Hampshire Democratic primary resulted in Johnson's stunning announcement that he would not seek re-election. When Sen. Robert F. Kennedy announced he was entering the race, Reagan — whose major political foe in the 1960s was in fact RFK — re-energized his own campaign.

Reagan brought in new campaign aides and wrote five white paper speeches attacking the foreign and defense policies of the Kennedy-Johnson administrations. During virtually every campaign press conference that spring, Reagan was asked about the Pueblo. In his revamped campaign film, "Ronald Reagan, Citizen Governor," Reagan launched his most scathing attack upon the multiple foreign and defense failures of the Kennedy-Johnson years. On May 11 in Hawaii, Reagan delivered his first white paper speech, The History and Significance of the U.S. Role in the Pacific. In the film and in his speech, Reagan made the Pueblo — its crew by this time was held captive for four months — a cornerstone of his fearsome attacks upon America's foreign affairs debacles under the Kennedy's and Johnson.

Reagan began by zeroing in on the fate of the USS Pueblo and its crew: "The seizure of the Pueblo and the kidnapping of our men is a humiliation we will not endure."

He then castigated America's lack of response, either to rescue the crew or punish the hijackers — by placing it within the broader context of how President John F. Kennedy had changed President Dwight Eisenhower's general policy — to rely on the threat of massive nuclear retaliation — to Kennedy's "flexible response:"

"This play had a seven-year run beginning with the Bay of Pigs and is closing with the humiliating theft of one of our ships and the kidnapping of 83 young Americans," he said. "The official explanation given for the inability of our air forces in the Far East to move out and support the Pueblo is that all the fighters on alert in Korea are equipped only for nuclear retaliation. Hasn't this been the most persistent claim of this administration? Hasn't their claim been that we have moved at a cost of $500 billion over these last few years from a nuclear freeze to one that would avoid the threat of the bomb and give us a flexible response? Now when the response is needed, we got no response at all!"

Reagan delivered his most detailed campaign attack on the Kennedy-Johnson administrations at Amarillo on July 19. At a press conference, he was asked what he would have done had he been president. Reagan answered that he would have dealt with the Pueblo crisis the same way as President Theodore Roosevelt had dealt with the Perdicaris affair many decades earlier. Off the cuff, Reagan reviewed the entire history of the incident (in which the Islamic chieftain Raisuli had kidnapped the naturalized American citizen, Perdicaris) and how TR's quick and firm response, "We want Perdicaris alive or Raisuli dead!" solved the crisis.

Reagan felt that the critical time period in any hostage crisis was the first day:

"I have felt that where we went wrong was ... the first 24 hours — that's the magic period. That's when this country should have said to them that we wanted the Pueblo and we wanted those men back or we would take whatever action was necessary to secure their return."

Reagan wanted America to have quickly threatened unspecified military action and to leave North Korea quaking in their beds and then freeing their captives. Indeed Reagan, who was being mentored on world affairs by Eisenhower, then revealed that he had discussed his idea with another world statesman.

"Former British Prime Minister Harold MacMillan of England said I was completely right and that 24 hours is the time."

During the late summer of 1968, Reagan was unsuccessful in his campaign for the 1968 GOP nomination, but the USS Pueblo incident was never far from his mind. By Christmas 1968, the crew finally was freed by their captors. When the ship's captain arrived home in San Diego, there on the pier to greet him was Gov. Reagan. Reagan proclaimed, "I just want to say how proud all of us here are." He expressed sympathy and joy to the crew and their families, "who knew the full measure of enemy brutality."

Ronald Reagan learned the lessons of the USS Pueblo well. Indeed, they would influence his handling as president of the freeing of the Iranian hostages as Reagan would take office in 1981, his firm and quick handling of the Achille Lauro hijackers, and the threats to American students in Grenada and America's subsequent invasion. These all had as their basis the same principle Reagan had derived from the mishandling of the USS Pueblo incident back in 1968.

Historian Gene Kopelson is the author of Reagan's 1968 Dress Rehearsal: Ike, RFK, and Reagan's Emergence as a World Statesman (Figueroa Press, 2016).

If you would like to write an op-ed for the Washington Examiner, please read our guidelines on submissions here.