A little bit of history’s unfinished business lurched unexpectedly out of the shadows last week. Philip Agee, the first – and some believe the only – CIA agent to betray the United States for ideological (rather than pecuniary) reasons, died of natural causes in a Havana hospital at 72.

He was, in one sense, so much a creature of the long Cold War with the Soviets and their surrogates that glimpsing the familiar, angular planes of Agee’s skeletal face there on the obituary pages was a bit like coming on one of those corpses periodically discovered in the bogs of Northern Europe, Iron Age men mysteriously wounded and sacrificed to a forgotten purpose.

Yet one important part of Agee’s strange and murky story is not a relic. In fact, it’s an urgent reminder of just how important it is that U.S. Attorney General Michael Mukasey push ahead with the investigation into the CIA’s destruction of the videotapes it made while interrogating accused al-Qaida terrorists. By the agency’s own admission, some of those sessions involved “enhanced” interrogation techniques (or what you and I would call torture), and coming to grips with the precise way in which the Bush administration surreptitiously adopted torture as an instrument of American policy is a critical responsibility.

I first met Agee in the mid-1970s, not long after he had published “Inside the Company: CIA Diary,” an account of his career as a rising young CIA agent in Latin America that also happened to reveal the identities of about 250 working American intelligence agents. In two subsequent books, designed to undermine the agency’s activities, he blew the cover on more than 2,000 U.S. agents in Western Europe and Africa. (In 1982, Congress passed the Intelligence Identities Protection Act specifically to halt Agee’s revelations.)

When I met him, as the Vietnam War was coming to an end, revelations of government mendacity – including CIA misconduct – had thrown the country into an uproar, a condition that provided Agee with just enough ambivalent cover. Had he committed an act of conscience or an act of betrayal?

To those of us who met or covered Agee, his death brings all this forcefully to mind, because the only part of the rather malleable explanation he offered for his conduct that ever seemed intelligible – or unambiguously credible – was his revulsion against the CIA’s complicity in torture. Note that word “complicity.” Although he came to hate the agency with a traitor’s ferocity, Agee never alleged that he or his CIA comrades tortured captives. It was bad enough, he would later say, that he had stood by while America’s Latin American allies tortured their own people. According to Agee, his conversion began when he fell in love with Angela Camargo Seixas, a beautiful Brazilian Marxist who had been arrested and tortured by her country’s military, which was then cooperating with U.S. intelligence.

His disaffection accelerated in Uruguay, where he listened as a young man, whose identity he had revealed to the local security forces, was tortured in the next room. In 1968, Agee ran CIA activities during the Mexico City Olympics. When the army massacred student protesters there, Agee told me he was tormented by the fact that the survivors were taken away and tortured to death.

We now know, of course, that Agee actively began collaborating with both Cuban intelligence and the KGB in the late 1960s. Soviet defectors Vasili Mitrokhin, a former KGB librarian, and Gen. Oleg Kalugin, who led the Soviet’s counterintelligence directorate, have confirmed it, as has the Cuban spymaster Pedro Riera Escalante.

At the end of day, Agee turned out to be just another person deluded into accepting one of the 20th century’s great lies – the notion that there was no choice but to take sides. Scandalized by the imperfections of the nation he knew best, he deceived himself into believing that a Faustian bargain is a choice.

There’s a contemporary lesson in that too. The Bush administration, and particularly the zealots on Vice President Dick Cheney’s staff, have tried their best to frighten the American people into a false choice – torture or insecurity.

If the life and death of Phil Agee signify anything, it’s that we need to recall that some values – like our instinctive revulsion at torture – are so fundamental to our American character that they can survive even treason.