Those charmless imitators seem to believe that the late President’s image can not only win primary votes, but even vanquish America’s enemies. As Rudolph Giuliani explained, a Reaganesque glare should be enough to scare the Iranian despot into surrendering any nuclear ambitions: “He has to look at an American President and he has to see Ronald Reagan. Remember, they looked in Ronald Reagan’s eyes, and in two minutes, they released the hostages.”

Such belligerent invocations of the old actor are standard fare on the G.O.P. primary circuit. The actual circumstances of American relations with Iran during the Reagan years—and indeed of security policy in general back then—were more complex and less inspirational (as Mr. Giuliani must know, unless he is now suffering from the onset of dementia).

The tough gunslinger described by the Republican candidates resembles the real Reagan about as accurately as his movie roles resembled his real life. It was strange to hear him mentioned in the context of Iran, the scene of the worst foreign-policy fiasco of his administration—and the topic that most clearly demonstrates the distance between right-wing fantasy and historical reality.

It was especially strange to hear those words uttered by Mr. Giuliani, who wants everyone to remember that he once served as a top official in the Reagan Justice Department, but who seems to have forgotten the criminal case and constitutional crisis known as the Iran-contra affair. But let’s begin at the beginning.

Available evidence strongly indicates that when the Iranian regime released American hostages in January 1981, within hours of the first Reagan inauguration, that decision had nothing to do with fear of the new President and everything to do with a prearranged deal. While no proof of that plot has ever emerged, the covert sequel that commenced three years later certainly arouses suspicion.

Between 1984 and 1986, the Reagan administration tried to free American hostages in Lebanon from their Shiite captors, not by confronting the terrorists militarily but by negotiating with their presumed Iranian sponsors. By then, Reagan had already retreated from Lebanon, withdrawing the Marines after the terrorist bombing of their Beirut barracks had claimed 241 American lives.

Around that same time, the White House concocted a pretext to invade the tiny Caribbean island of Grenada, which distracted public attention from the American humiliation in the Middle East.

Instead of retaliating against Iran or any of the organizations that claimed responsibility for the Lebanon attack, Reagan approved a secret initiative to improve relations with the Iranian leadership by shipping advanced missiles to them. The immediate objective was to get the Iranians to lean on Hezbollah in Lebanon to release a group of six American hostages. Seeking to advance the discussion, National Security Advisor Robert (Bud) McFarlane visited Tehran, carrying a Koran and a cake as tokens of Presidential esteem. Meanwhile, the profits from the arms transactions—which were conducted by private citizens working with White House and C.I.A. personnel—were diverted to finance the contra rebellion in Nicaragua.

These bizarre intrigues breached U.S. law and policy in myriad ways, including repeated violations of the statute forbidding aid to regimes that support terrorism. At first Reagan tried to deny that he had “traded arms for hostages,” then reluctantly confessed many months later while seeking to blame his subordinates.

While there was much more to the scandal that nearly ended Reagan’s Presidency—including the starring role of neoconservatives who have since masterminded another, worse disaster—the basic outline is clear: Terrorists killed our troops, and Reagan responded by retreating from Lebanon, kowtowing to the terrorists’ sponsors, meeting their demand for advanced weapons and pleading for the release of our hostages.

It is easy to imagine how the Republicans would have reacted to this kind of behavior by a Democratic President—and how they would recall such behavior today. Words such as “strong” and “resolute” would not leap to their lips.

With Reagan, however, myth replaces memory. The truth is that he saved his Presidency by ousting the hawks and neoconservatives who had almost destroyed it, and by entering into the unprecedented negotiations with Soviet leader Mikhail Gorbachev that helped to end the Cold War peacefully. For that momentous decision, he suffered angry public attacks by many of the same conservatives who lionize him today.

The macho posturing in Reagan’s name is comical and demeaning, but not without danger. Let’s hope this is all just campaign bluster—and that none of the pretenders who may someday achieve power believe in their own fakery.