Talking to the Taliban is tough for many Americans to accept. Dick Cheney was speaking for many when he said, “We don’t negotiate with evil; we defeat it.” And yet, says Jonathan Powell, Tony Blair’s former chief of staff, he’s dead wrong. In a new book, “Terrorists at the Table: Why Negotiating is the Only Way to Peace,” Powell argues forcefully that historically, conflicts like the one in Afghanistan have ended only through negotiations and not military victory. Powell is no peacenik, having been an architect of Britain’s support for the wars in Afghanistan and Iraq. Nor is he soft on terrorism. His father, a military man, was wounded by the Irish Republican Army. His brother was on that group’s death list for eight years . When he first met Gerry Adams of Sinn Féin, Powell refused to shake his hand.

But over the course of his decade as Blair’s most important aide, Powell came to recognize that terrorism cannot be solved exclusively or largely by military means. He quotes Hugh Orde, the former chief constable in Northern Ireland, who rightly says: There is “no example that I know of, of terrorism being policed out” or eliminated through the use of force.

Governments are loath to talk to terrorists. This is understandable because they regard the groups as barbaric, worry about legitimizing brutality and remain convinced that military force can defeat or at least cripple them. But, Powell points out, most governments end up talking to terrorists. The British government saw the Mau Mau in Kenya in the 1950s as a “conspiracy based on the total perversion of the human spirit” — “subhumans” with “death as their only deliverance,” in the words of Britain’s colonial secretary at the time. And yet it ended up talking to them. The same pattern emerged with the IRA, the Basque separatists, the African National Congress and the Colombian FARC. Israel has even negotiated with Hamas on prisoner exchanges. “I don’t mind the hypocrisy of governments on the subject of talking to terrorists,” writes Powell, “but I do mind the fact that we never seem to learn from past experiences, often with devastating consequences.”