He made liberal Israelis face the possibility that the Zionist idea was flawed in its conception.

Until his assassination Monday, Meir Kahane's most enraging quality for many liberal Israelis was his surgical ability to expose and pierce their most terrifying contradictions.

These Jews of goodwill -- ready more than almost any people in any nation in the world to risk their country's survival and their own in a dangerous gamble for acceptance and peace -- recognized in Kahane's rantings a core of deeply painful truth. Even if the gamble they advocated were risked, even if the occupied territories were given up and even if, against the odds, the resulting Palestinian state would let them live in peace, the Arabs left in Israel itself -- all of them citizens of the democratic Jewish state and now more opposed than ever to the existence of Israel -- might, as Kahane warned, grow numerous enough within a few decades to undo by their votes the essential Jewish character of the country.

In the long run, Kahane argued, even if Israel gave up the West Bank and Gaza, it couldn't hold on to both its democratic identity and its Jewish one. Liberal Israelis, he insisted, had to choose one identity or the other.

Most such Israelis chose, instead, to get angry with Kahane. After Jews had lived at the mercy of hostile Christian and Moslem populations for many centuries -- after they had been massacred repeatedly because of their religion and after they had suffered in this century the most colossal massacre in all of human history -- the idea that they might not be able to sustain a Jewish state within their ancient homeland, one in which they could determine their own future and defend themselves as Jews, was for these Israelis astonishing.

No less astonishing to these Israelis, though, was the idea that such a Jewish state could not be built on the democratic principles that Western political experience had shown to be the most just, humane and stable foundations for governance.

Rather than having to consider the need to choose between one astonishment or the other -- between admitting that the Zionist idea of creating a Jewish state might have been flawed in its very conception, or admitting that in order to sustain such a state they might have to suspend the democratic and secular principles that were at the heart of that idea -- these Israelis decided to avoid recognizing the very possibility of the contradiction that might require such a choice. When Kahane insisted they had to do so, they reacted with precisely the kind of angry and wholesale rejection that we all tend to use when we're provoked by challenges that contain kernels of threatening and unwanted truth.

That Kahane provided enough cause to reject him helped. He was indeed a racist who appealed to the lowest passions in the Israeli electorate. He expressed views about Palestinians and advocated actions against them, particularly their "transfer" to Arab countries, that are simply incompatible either with current Western democratic standards of with traditional Israeli ones. They were, to be sure, compatible with the standards of rhetoric and behavior toward Jews in most Arab countries and compatible as well with practices that have been pursued frequently by other countries faced with similar demographic challenges; but most Israelis still wanted to hold themselves to standards that were democratic and liberal rather than local and inhumane.

So it was easy for these Israelis and their American friends to reject Kahane's challenging demographic and social analyses, because those analyses were part of the larger package of Kahanism that was fouling Israeli society and besmirching the Jewish traditions of justice, kindness and mercy. And this rejection made it easier for such Israelis to continue living in Israel without having to come to terms with the possibility that those analyses, and the contradictions they suggested, might have to be taken seriously.

Kahane's assassination, and the discussion it will inevitably provoke of his arguments and ideas, will once again bring to the fore the inconsistencies and perplexities in the identity, nature and future of Israeli society he has so troublesomely articulated. Many Israelis will, no doubt, respond to them once again as they have in past -- with anger and rejection.

But in the long run, the responses by Israelis to Kahane's challenge must be more useful and serious than that. The man's policies are unacceptable, and as an Israeli attorney general once put it, loathsome; but his arguments must be heard, examined, and if they contain any truth, dealt with. A political arrangement that makes possible an Israel that can sustain, indefinitely and confidently, its character as both a Jewish state and a democratic one must be found. Such an arrangement, if it preserves Israeli security as it provides greater opportunity for Palestinian self-governance, would fulfill at least some of the aspirations of the Palestinians even as it fulfills at least some of the aspirations -- and averts the most lethal of the contradictions -- of the Israelis.

Clearly, for such an arrangement to be successful, it would have to take into account not only the Palestinians in the occupied territories but also the ones in pre-1967 Israel; demographic probabilities would have to be calculated with care, concern and realism. It's altogether possible, in fact, that such a calculation would show that Kahane was wrong in his warnings that Israel's own Arab citizens might be able, someday, to vote out, or at least undermine, the Jewish state. Such an arrangement would, in any case, have to ensure the continued viability of full democracy in an Israel that remains the Jewish homeland. Just how such viability could be ensured is by no means clear, but its evident necessity is perhaps the only beneficial -- and surely unintended -- legacy of Meir Kahane.

In 1984, in Jerusalem, soon after he was elected to the Knesset by 1.3 percent of the Israeli electorate, Kahane told me in an interview that he expected to be assassinated by an Israeli Jew. That he was reported to be assassinated by an Arab living in America reflects, in some ways, the changes that have taken place during the past six years, particularly the widening of the Arab-Israeli conflict. These changes have been profound ones, and presage ones still more profound if Jews as well as Arabs fail to disenthrall themselves from the comfortable but lethal paralysis that makes compromise ever less likely and Kahane's dark and descending vision ever more possible. The writer is a senior scholar at the Woodrow Wilson Center.