This formula has been the basis of peace talks for more than two decades, and no one has come up with a realistic formula to replace it. That's why there is a desperate need for fresh thinking about what to do if it dies.
Of course, it's hard to think of a time less likely to produce a final agreement between Palestinians and Israel. The Arab world is in disarray, and there is an ongoing struggle within Islam. The strong Arab neighbors that Israel would require to guarantee the future of a weak Palestinian state no longer exist. And the issue of Iran's nuclear program looms over all.
But the reason the two-state solution has become passe goes deeper than the press of current events. It has to do with the passage of time and changed facts on the ground.
The generation of Palestinians and Israelis that negotiated the Oslo accords in 1993 had faith in the two-state concept. Its strongest Palestinian advocates had served years in Israeli prisons as secular Fatah activists and knew Hebrew. They believed two states was the best deal the Palestinians would get.
Israeli activists and intellectuals had long contacts with their counterparts, at a time when Palestinians could travel freely inside Israel and vice versa. Unlike now, peace negotiators were discussing the nuts and bolts of ending the conflict: for example, how to divide Jerusalem into two capitals, and how to resettle hundreds of thousands of Palestinian refugees in third countries.
Those days seem like ancient history now.
There's no room to list all the reasons the Oslo Accord failed, including Palestinian suicide bombers and Israel's vast settlement project on the West Bank. Suffice it to say that today, Palestinians and Israelis are mostly cut off from each other by walls and fences, and their youths rarely meet, except at Israeli military checkpoints.
So it's unsurprising that the younger generation is more skeptical about two states than their parents. The two-state solution is still the most popular option on both sides, but that support is waning. A poll by Zogby Research Services showed barely one-third of Israelis and Palestinians believe a two-state solution is feasible, while younger Israelis take harder-line positions than their elders.
A similar generation gap emerged from a December poll by the Palestinian Center for Policy and Survey Research; it found that, while 65 percent of Palestinians over 50 still supported the two-state idea, only 47 percent of those 18-34 did.
The Times wrote that Abbas' own son Tareq, an apolitical businessman, has told his father that current negotiations are futile; he is part of a growing number of prominent Palestinians, many under 45, who argue they should seek equal rights as citizens inside one state stretching from the Jordan River to the Mediterranean Sea.
This brings us to the options other than two states. If Palestinians got full rights inside a single state, its Arab citizens would soon outnumber (and out-vote) Jewish Israelis. That would mean the end of the Jewish homeland, and would guarantee permanent civil war.
A hawkish Israeli version of the one-state solution is equally unrealistic; it argues that Palestinians would be satisfied to live without political rights in cantons essentially controlled by Israelis.
The one-state solution is a non-starter: Either Israel would remain an eternal occupier or it would no longer be a Jewish state.
Some Israelis have suggested the country unilaterally withdraw from populated areas of the West Bank, but this would solve little; those areas would be economically and politically unviable, becoming hotbeds of protest or rockets, as happened with Gaza. Others argue that Jordan might be persuaded to take control of segments of the West Bank; that hoary idea is anathema to Jordan's monarch and people.
So Obama was not off base when he told the Atlantic's Jeffrey Goldberg: "I have not yet heard . . . a persuasive vision of how Israel survives as a democracy and a Jewish state . . . in the absence of . . . a two-state solution. Nobody has presented me a credible scenario."
The problem is that there is none, which is why the negotiators may ultimately produce a vague framework that keeps the talks going, to buy time to figure out what to do if they end.