The transformation of historian Tony Judt from being an advocate of Israel as a young man into one of the most distinctive intellectual critics of the country was an interesting interlude in the otherwise dreary disputation surrounding the Palestinian-Israeli conflict.

Judt’s death last week, from complications due to amyotrophic lateral sclerosis, a motor neuron disorder, was little surprise, and was foreshadowed by the decision of the New York Review of Books to publish an essay by him in each of its recent editions, as if admitting that his time was short. By then, Judt’s affliction had, regrettably, transformed him into a mind without a body.

It was a brilliant mind, but when it came to the destiny of Israel and the Palestinians, Judt quickly found himself a prisoner of familiar byways – a paragon to those siding with the Palestinian cause and an object of censure for supporters of Israel. The primary reason was an essay he had written in 2003, again for the New York Review of Books, titled Israel: The Alternative.

In the article, Judt echoed the views of his friend Edward Said in supporting a binational state in which Israelis and Palestinians could live together. “It is not such a very odd thought,” he wrote. “Most of the readers of this essay live in pluralist states which have long since become multiethnic and multicultural.” In a later introduction that he wrote to a posthumous collection of Said’s articles, Judt described Said’s adoption of binationalism as the consequence of “hardheaded pragmatism”, the result of his belief that Israel would never quit the West Bank, or do so in such a way that would leave behind a governable state. As a result, there was “no alternative to reciprocal territorial self determination for Jews and Arabs alike”.

Judt had defended his own embrace of binationalism in a slightly different light, one familiar today for being voiced even by Israel’s defenders – for example, the American vice president, Joe Biden, when he visited Israel last March. As Mr Biden put it: “It’s no secret the demographic realities make it increasingly difficult for Israel to remain both a Jewish homeland and a democratic country in the absence of the Palestinian state.” This dilemma – whether Israel can remain democratic while abusing and denying viable statehood to an expanding Palestinian population that will become a majority in the coming generations – was at the heart of Judt’s critique of a state whose army he had served in during the time of the June 1967 war.

Yet Judt had no illusions about a two-state project, and in this he parted ways with those like Mr Biden. One passage in Israel: The Alternative explained why, and I suspect provoked the greatest animosity among his detractors: “[Israel] has imported a characteristically late-19th century separatist project into a world that has moved on, a world of individual rights, open frontiers, and international law... Israel, in short, is an anachronism.”

By placing Israel in the train of 19th century nationalisms, Judt deflated the messianic impulses that took hold of the country after its heady victory of 1967. Here was a state like any other, he implied. In Dark Victory: Israel’s Six-Day War, Judt recalled the insular debates on such topics as applied socialism that kibbutz members engaged in during the early 1960s, a transposition into the Middle East of a largely European discussion. “Not surprisingly, Arabs figured very little in this world,” he wrote.

Judt and Said often came across more as intellectual heirs of 19th century bourgeois liberalism than enemies of 19th and 20th century colonialism. And perhaps that’s where to find the flaw in their binational proposal. Despite Judt’s efforts to defend Said’s binationalism as pragmatic, for both men a Jewish-Arab state seemed primarily grounded in an ideal of positivist liberal cosmopolitanism, the same that allowed Judt to describe Israel as an anachronism.

Here Judt’s argument hit a snag. His assessment of Israel was that the country moved to the right after 1967, toward a combination of greater political intolerance and a sense of territorial entitlement. On the Palestinian side, too, there was a hardening of positions, with Hamas gaining power by rejecting the Oslo process and its core principle of a two-state solution based on mutual recognition. To assume that such conditions are propitious for the establishment of a binational state is counterintuitive, even absurd.

That is why Judt had the symptoms right, but not the cure. His views were born of desperation and a compulsive search for a way out. But Judt was no fool; in favouring a near unattainable binationalism, it could be that he was admitting a solution didn’t exist. Israel, the stronger party, has offered no realistic end game to deal with the Palestinians, because it does not have one.

Judt became a lighting rod of condemnation from Israel’s defenders. But in attacking the cure of binationalism, they also avoided addressing his accurate reading of the symptoms. How short-sighted. Israel is further than ever from an answer to the impasse, and Tony Judt’s merit was to hammer this home by bringing a tolerant, liberal historical sensibility to his interpretation of a debilitating stalemate that may soon yield another long war.