Throughout this horrible week, my mind has repeatedly flashed back to Dec. 23, 2000. That was the day the Palestinians were offered a path to having their own nation on roughly 95 percent of the land in the West Bank and 100 percent of the land in the Gaza Strip. Under that outline, Israel would also swap some of its own land to compensate the Palestinians in exchange for maintaining 80 percent of its settler presence in the West Bank.

The Palestinians would control, in President Bill Clinton’s formulation, “Arab areas” of East Jerusalem. And on the most sensitive religious sites, there would have been divided sovereignty or jurisdiction, with Palestinians controlling the Haram al-Sharif (including the Aqsa and Dome of the Rock mosques) and Israel controlling the Western Wall and the holy space of which it is a part. There would also be a return of many refugees into the new Palestinian state (without the right of return to Israel itself).

There were a million complexities — and many errors made by the Israeli, Palestinian and American sides along the way. But this offer pointed the way to the sort of fair solution negotiators had been struggling their way toward for years. It is hard to see this kind of option ever being on the table again. And the Palestinians let it slip away.

This memory comes hauntingly back because the misery that Palestinians and Israelis are now enduring did not have to happen. They could have reached some kind of moderately effective arrangement, which would have given the two nations a chance to pursue their own destinies.

Another reason I think back on this history is the way a simplistic oppressor/oppressed, colonizer/colonized, “apartheid Israel” narrative has been imposed on this conflict.

The real history is much more complicated. It is the story of the Palestinians who were offered a state in 1947 that the Arab states opposed. More recently, it is the story of flawed human beings on both the Israeli and Palestinian sides, who were confronted with a devilishly complicated situation. They worked doggedly to secure peace and made real, if stumbling, progress toward that end. It is the story of how radicals on both sides undermined their efforts, leading to the bloodshed we see today. This is what happens when the center does not hold.

The drive toward that 2000 peace offering began at the Madrid peace conference of 1991. Throughout that decade, there were a series of major peace efforts: the Oslo process, the Cairo Agreement, Oslo II, the Hebron Protocol, the Wye River Plantation meeting.

Along the way, the momentum was nearly derailed. An Israeli settler assassinated Prime Minister Yitzhak Rabin as he strode toward peace. There were cascades of bombings authored by Hamas and other terrorist groups.

But Israelis continued to support a two-state solution. On May 17, 1999, the Labor Party leader, Ehud Barak, running on an aggressive peace platform, defeated Benjamin Netanyahu in the race for prime minister.

Bill Clinton hosted an Israeli-Palestinian summit at Camp David in July 2000. In many ways that summit was premature. But as the chief U.S. negotiator at the time, Dennis Ross, told me this week, Barak led “the most forthcoming government in Israel’s history,” and Clinton seized the opportunity.

The summit failed to yield an agreement, and the enemies of peace struck back. Ariel Sharon took a stroll on the Temple Mount — where Haram al-Sharif stands and non-Muslim entry is restricted — that provoked Palestinian rage. The Palestinian leadership launched the second intifada, bringing a reign of terror to Israeli streets.

Still, Clinton and negotiators persisted with meetings at Sharm al-Sheik. By the end of the year, Clinton brought the two sides to the White House. At the pivotal meeting in December, he slowly read aloud the peace plan that would come to be known as the Clinton Parameters. It called for uncomfortable sacrifices from both parties but gave each side what the U.S. negotiators believed they needed.

A few days later, the Israeli cabinet voted to accept the plan. Yasir Arafat did what he generally did. He never said no, but he never said yes. The Saudi and Egyptian ambassadors in Washington strongly pressured him to agree to a deal, but perhaps feeling pressure from back home or sensing where Palestinian public opinion was or feeling that the provisions for the refugees were insufficient, Arafat dallied. Momentum was frittered away. Just before Clinton left office, he had one of his final conversations with Arafat. Arafat told him he was a great man. According to his memoir, Clinton replied: “I am not a great man. I am a failure, and you have made me one.”

Arafat’s nondecision further discredited the peace camp in Israel, suggesting that if he wouldn’t go for this, he would never go for any negotiated settlement. Sharon soared to victory in the next election. In “The Missing Peace,” Ross’s definitive 872-page history of this period, Ross concluded that Arafat never transformed himself from a guerrilla outsider to the kind of leader capable of forming and governing a nation. The Palestinians “surely were betrayed in the past, and they surely have suffered,” Ross wrote. “But they have also helped to ensure their status as victims. Never seizing opportunities when they presented themselves. Blaming others for their predicament. Declaring unmistakable defeats as victories.”

In the ensuing decades, Israel and its settlers have expanded their occupation of the Palestinian territories, Israeli politics have shifted sharply rightward, and the Hamas fundamentalist death cult has grown stronger and more satanically daring.

As I went back and revisited all these events, I was struck by how negotiators on both sides were immersed in resolving practical issues. Now politics is mostly theater and psychodrama. Hamas and its followers cultivate the fantasy that Israel, a permanent Middle Eastern nation, will magically cease to exist. Its terrorists seek to avenge the wounds of injustice and humiliation with mass murder, without anything remotely resembling a firm plan to improve the quality of Palestinian lives.

And in the United States, some students and activists create rally posters with paragliders to celebrate the murderers who descended on the Israeli music festival. It’s all vicious posturing, to make people feel avant-garde and self-righteous, no matter how many decades of real human suffering lie ahead.