On Jan. 22, 1995, Israeli Prime Minister Yitzhak Rabin was due to speak at Yad Vashem, the heartbreaking Holocaust memorial above Jerusalem. It was 50 years since the liberation of Auschwitz, a time to remember the suffering of the Jews and the great accomplishments of the state of Israel, which had won its fight for independence in 1948.

Rabin had fought in that war and rose to be chief of staff of the Israel Defense Force when it beat all Arab comers in 1967, taking Gaza, the Sinai, the West Bank, and the holy precincts of East Jerusalem in just six days. A secular, pragmatic soldier, a national hero but not a great politician, Rabin sometimes seemed oblivious to the virulent currents of fanaticism that ran through Israeli society. He resisted traveling in a bulletproof car, and he refused to wear a bulletproof vest.

On that same day in January 1995, as Dan Ephron tells us in his riveting new book, Killing a King: The Assassination of Yitzhak Rabin and the Remaking of Israel, a group of Israeli students was on its way to confront Rabin at Yad Vashem. The students would hold up placards calling him a murderer, likening him to a Nazi, denouncing him for signing, 16 months earlier, a tentative peace treaty with Yasser Arafat of the Palestine Liberation Organization. They blamed him for ceding control of lands they believed God gave them in Gaza and Judea and Samaria (the West Bank).

They also blamed Rabin for a rising wave of terror attacks by Hamas, an extremist organization that opposed the peace accords as much as they did and which neither Rabin’s nor Arafat’s services could control. And they debated among themselves whether religious law would condone the killing of Israel’s treasonous prime minister. On their bus winding its way through the hills of Jerusalem, the conversation was passionate and, as students’ conversations often are, it ultimately was academic. Except for one of them.

Yigal Amir, 24 at the time, had his Beretta 9mm tucked into his belt. Earlier in the day he had gone to synagogue and recited quietly to himself the vidui, the confessional prayer Jews say before death. He had told people around him many times that he thought Rabin should be killed and even that he planned to kill him. But Amir hadn’t told them it would be that day. And anyway, no one, not even a paid provocateur and informant for the Shin Bet, had believed him.

Then, death struck elsewhere. At a bus stop at Beit Lid junction in central Israel, where Israeli soldiers gathered to go back to their units after the weekend, two suicide bombers from Islamic Jihad blew themselves up, killing 21 Israelis.

Rabin went to the scene at Beit Lid instead of to Yad Vashem. And that day, his would-be killer never had a chance to shoot.

As it happened, I was in Israel just then, reporting on the peace process, and I arrived at Beit Lid not long after Rabin had been there. He’d been met by Israelis shouting “Death to Arabs.” Orthodox volunteers were still picking up bits of flesh left by the suicide blasts, and it seemed that there might not be much peace left to cover.

And yet the process begun with secret talks in Oslo and a White House ceremony in 1993 somehow kept going. It survived the slaughter of Muslim worshippers in Hebron’s Tomb of the Patriarchs by the Jewish settler Baruch Goldstein. It survived the Beit Lid attack and other atrocities by Hamas and Islamic Jihad. Doggedly, Rabin and Arafat kept trying to make it work, kept looking for hope, and sometimes found it. Investments were pouring into Israel, its long isolation seemingly a thing of the past, its stock market soaring. Money was even flooding into the Palestinian territories, where the dream of shaking off Israeli occupation looked like a plausible, even imminent reality. Jordan signed a solid peace treaty with Israel. Syria looked like even it might do the same.

Indeed, it’s easy to forget today how much progress was being made back then. Some cynical journalists used to covering wars even complained that the Middle East was suddenly rather boring.

Then, on the night of Nov. 4, 1995, during a huge peace rally in Tel Aviv, Amir caught up with Rabin and pumped two bullets into his back, ending, as we now know, the last, best chance for an enduring resolution of the Middle East conflict.

In Killing the King, Ephron has given us a thriller that is deadly accurate history as we follow the lives of Rabin and Amir over the course of those two years between the White House ceremony and the assassination.

Many moments in the narrative have a cinematic quality: Rabin flying to Washington for the signing ceremony and learning midflight that a commuter bus in Ashkelon has been attacked by a Palestinian from Gaza; the announcement of the Nobel Peace Prize for Arafat, Israeli Foreign Minister Shimon Peres, and Prime Minister Rabin—just as a rescue mission is under way to try to save an Israeli soldier taken hostage near Jerusalem. And all the while, Rabin is being stalked by Amir, this bright young son of Yemeni immigrants who is convinced he can “fathom God’s will” and “come to the help of the Lord” by murdering the prime minister.

The portrait of Amir is based on interviews with his acquaintances and family (his older brother Hagai was a co-conspirator, but did not participate in the shooting), and on the many hours of Amir’s taped post-arrest interrogations and confessions. During those he had been in a celebratory mood, asking for schnapps to toast his accomplishment. The result is a granular portrait, up close and and very personal, and as a study in religious fanaticism—the deadly convictions of a true believer—it could be applied ecumenically to terrorists the world over who, frustrated in their lives, imagine they can become agents of the Almighty.

“There’s a strong conflict inside him between the longing for sensual and emotional satisfaction and his commitment to a religious and ideological way of life—an ideology that demands sacrificing all material pleasures,” wrote a psychologist after spending several hours with Amir over two days following his arrest. “He feels a sense of guilt about the longing.”

But typical as he may be, few other terrorists have had the impact Amir had, because while he may have acted alone, he did not act in isolation. In the months before Rabin was killed, after all, it was not only radical religious students who denounced the peace-making prime minister as a traitor.

As Ephron writes, “The ugly invective came not just from the political margins but from the top echelons of the Likud Party. Ariel Sharon, who had founded Likud and now served as one of its senior deputies in parliament, favored the World War II comparisons. ‘What’s the difference between the Jewish leadership in the ghetto and this government?’ he said in a typical remark, months after the Oslo signing. ‘There, they were forced to collaborate. Here they do it willingly.’ [Benjamin] Netanyahu generally stuck to calling Rabin a liar and accusing him of enabling violence against the settlers. ‘They [Hamas] receive signals from both the government and the PLO to kill Jews in Judea and Samaria.’ Others said much worse.”

Ephron was there in the crowd the night of the shooting. He covered Amir’s trial day after day. Later, as a colleague of mine at Newsweek, he wrote about the ferocious second intifida, the building of walls, the steady erosion of hope and then, after a stint away from Israel covering U.S. national security, he returned in 2010 to discover a country that was prosperous and complacent. “The fact that life in Israel was good despite the absence of peace meant there was little incentive to revive the process.”

“In killing the Israeli leader,” Ephron concluded, “Amir had done better than the assassins of Lincoln, Kennedy, and King, whose policies had gained momentum as a result of their murders. During the years of his imprisonment, he had the satisfaction of watching Rabin’s legacy steadily evaporate.”

A few months after Rabin’s murder, Netanyahu won his first term as prime minister of Israel. Sharon eventually was elected, as well. And Netanyahu, re-elected in 2009, is now in his fourth term. Hamas is firmly in control of Gaza, despite several brutal wars. The West Bank is behind a wall. The Palestinian Authority has proved powerless to stop the encroachment of Israeli settlements, as has the international community. The idea of a two-state solution to the Israeli-Palestinian conflict is all but dead, but no one wants “apartheid,” the word used by Rabin to describe one state with a second-class Arab majority. And in recent weeks a spate of knife attacks by Palestinians is talked about as a prelude to a new intifada. The complacent illusion of peace is fading.

The question today, 20 years later, is not what things might have been like if Rabin had lived. It is enough just to look honestly at the way they are now: Politics in the Holy Land are no longer based on hope but on fear. And all around are young men who will tell us they have fathomed the will of God.