Nobody with a functioning memory should be too quick to condemn Jimmy Carter for daring to speak with the leadership of Hamas, as nearly everyone along the American political spectrum suddenly has felt obliged to do. From Condoleezza Rice and John McCain to Barack Obama and Hillary Clinton, along with every congressional backbencher in both parties, expressions of disapproval have rained down upon the former president, who is old enough and tough enough to pursue his own beliefs to their logical conclusion.

“The United States is not going to deal with Hamas,” said the secretary of state, “and we had certainly told President Carter that we did not think meeting with Hamas was going to help.” The justification for that policy was explained helpfully by Obama, whose willingness to meet with foreign adversaries does not extend to Hamas, at least not during the primary season. The Illinois senator “does not support negotiations with Hamas until they renounce terrorism, recognize Israel’s right to exist, and abide by past agreements,” according to a spokesman for his presidential campaign.

As for McCain, he reacted reflexively and demagogically, which should come as no surprise. He denounced any engagement with Hamas as a “grave and dangerous mistake” and scorched Carter for meeting with “a terrorist group that has also killed innocent Americans.” A moronic congresswoman from North Carolina — who will have to live a very long time before she achieves a tiny fraction of what Carter has — proposed to revoke his passport.

Certainly Carter understands the nature of Hamas, an Islamist group not so different in its orientation from the radical students whose takeover of the U.S. Embassy in Tehran ultimately ended his presidency. What he also understands these many years later is that those once shunned as terrorists and criminals, forever beyond redemption, may eventually be recognized as the only possible partners in negotiation. For that, of course, is the very transformation he has observed in the Palestine Liberation Organization during the past three decades.

When Carter hosted the historic Camp David meetings that established peace between Israel and Egypt, the Jewish state’s prime minister was the late Menachem Begin, a former terrorist who firmly declared that he would never talk with Yasser Arafat and the PLO. Even as the Palestinians quietly began to consider the notion of a two-state peace settlement, American and Israeli policymakers could hardly contemplate any engagement with Arafat, whose responsibility for atrocious attacks on civilians was as clear as his commitment to driving the Jews into the sea. Indeed, Israel’s leaders regularly proclaimed that they would never talk with Arafat under any circumstances because of the Jewish blood on his hands.

Then things changed, slowly but irrevocably. Today the PLO leadership, legatee of the unmourned Arafat, is not only welcomed but also financially supported by the United States, with its shaky authority on the West Bank bolstered by the Israel Defense Forces. The government of Israel and the Palestinian Authority remain far from the final agreement that would achieve a just peace, but each acknowledges the legitimacy of the other.

This short history lesson is not meant to minimize the obstacles to a real peace. Most prominent among those obstacles is Hamas, which will continue to undermine and embarrass Palestinian President Mahmoud Abbas so long as it is excluded from any and all diplomacy. Despite the repugnant ideology and brutality of the Hamas leaders, there is no doubt that the Islamist organization enjoys substantial popular support, even among Palestinians who do not share its religious worldview.

So there can be no sustainable deal between Israel and the Palestinians that is not accepted by Hamas.

Yet our current policy not only rejects any direct discussion with the Islamist party, but condemns any effort to learn what might bring them into the diplomatic process — or induce them to accept a negotiated settlement between the Palestinian Authority and Israel. Instead, we would require them to effectively surrender every point before we will even talk to them. It is the same mindless policy once directed by the White House toward our adversaries in Iran and North Korea until its uselessness became too obvious to ignore.

With ongoing violence in Gaza, Carter’s critics have already pronounced his mission a failure. But he elicited an official pledge that Hamas would honor a semi-permanent truce under certain conditions and accept a Palestinian referendum to ratify a peace settlement. That hint of moderation, halting and reversible, suggests that he may yet be vindicated.

Joe Conason writes for the New York Observer.