Israel's prime minister, Ariel Sharon, has suffered a massive brain hemorrhage; at the very least, his long political career appears to be over. What does that mean for Israeli politics and for Arab-Israeli relations?

Basically, it signals a return to business as usual.

Since the State of Israel came into existence in 1948, two points of view on relations with the Arabs have dominated its political life, represented by (as they are presently called) Labour on the left and Likud on the right.

Labour argued for greater flexibility and accommodation with the Arabs, Likud called for a tougher stance. Every one of Israel's 11 prime ministers came from the two of them, not a single one came from the plethora of others. The two parties together suffered a long-term decline in popularity but they jointly remained the pivots and kingmakers of Israel electoral life.

Or so they did until six weeks ago. On Nov. 21, Sharon left Likud and formed his own party, called Kadima. He took this radical step in part because his views vis-à-vis the Palestinians had evolved so far from Likud's nationalist policies, as shown by his withdrawal of Israeli forces and civilians from Gaza during mid-2005, that he no longer fit there. Also, he had attained such personal popularity that he attained the stature to found a party in his own image.

His move was exquisitely timed and enormously successful. Instantly, the polls showed Kadima effectively replacing Labour and Likud. The latest survey, conducted by"Dialogue" on Monday and published yesterday, showed Kadima winning 42 seats of the 120 seats in the Knesset, Israel's parliament. Labour followed with 19 seats and Likud trailing behind with a dismal 14.

Kadima's stunning success turned Israeli politics upside-down. The historic warhorses had been so sidelined, one could speculate about Sharon forming a government without even bothering to ally with one or other of them.

Even more astonishing was Sharon's personal authority in Kadima; never had Israel witnessed the emergence of such a strongman. (And rarely do other mature democracies; Pim Fortuyn in the Netherlands comes to mind as another exception.) Sharon quickly lured to Kadima prominent Labour, Likud and other politicians who shared little in common other than a willingness to follow his lead.

It was a daredevil, high-flying, net-less, bravura, acrobatic feat, one that would last only so long as Sharon retained his magic touch. Or his health.

I was skeptical of Kadima from the very start, dismissing it just one week after it came into existence as an escapist venture that"will (1) fall about as abruptly as it has arisen and (2) leave behind a meager legacy." If Sharon's career is now over, so is Kadima's. He created it, he ran it, he decided its policies, and none else can now control its fissiparous elements. Without Sharon, Kadima's constituent elements will drift back to their old homes in Labour, Likud, and elsewhere. With a thud, Israeli politics return to normal.

Likud, expected to slip into a dismal third place in the March voting, stands the most to gain from Sharon's exit. Kadima's members came disproportionately from its ranks and now Likud conceivably could, under the forceful leadership of Benjamin Netanyahu, do well enough to remain in power. Likud's prospects look all the brighter given that Labour has just elected a radical and untried new leader, Amir Peretz.

More broadly, the sudden leftward turn of Israeli politics in the wake of Sharon's personal turn to the left will stop and perhaps even be reversed.

Turning to Israeli relations with the Palestinians, Sharon made monumental mistakes in recent months. In particular, the withdrawal of all Israelis from Gaza confirmed for Palestinians that violence works, prompting a barrage of rockets on Israeli territory and an inflammation of the political temperature.

As Israel settles back to a more normal state, with no politician enjoying Sharon's outsized popularity, governmental actions will again come under closer scrutiny. The result is likely to be a less escapist and more realist set of policies toward the Palestinians and perhaps even some forward movement toward a resolution of the Israeli-Palestinian war.