By Tarik Kafala
BBC News website
Without Ariel Sharon, further disengagement will not be possible
Presuming the worst regarding Ariel Sharon's health, we are looking at a vastly significant moment of change for Israel, the Palestinians and the wider Middle East.
Like him or loathe him, the Israeli prime minister is a political colossus for Israelis. He has been at the centre of Israeli political life since the state's creation.
A controversial figure throughout his military and political career, he was once forced to resign as defence minister over the massacres by Christian militiamen of Palestinians in the refugee camps around Beirut in 1982.
But he is also currently the only Middle Eastern leader with anything like a plan that might bring about a settlement between the Palestinians and Israelis.
From a position of great strength over the Palestinians he has been imposing a plan that his critics, Palestinian and Israeli, see as a recipe for further violence rather than a settlement.
Without him, these are very worrying times for anyone concerned with what has been for more than 50 years the festering wound at the centre of conflict in the region.
Mr Sharon has always pursued his view of what is best for Israel with absolute determination.
Sharon and Yitzhak Rabin reached the same conclusion on the occupied territories
His mission was once to build vast settlements in the occupied West Bank and Gaza. Mr Sharon was one of the strongest advocates of settlements for strategic territorial reasons, not for religious ones.
But as the military threat to Israel from its neighbours lessened, another threat emerged - the growing number of Palestinian Arabs in the areas under Israeli control.
For Israel to remain a state for the Jewish people, some of these areas had to be given up.
This was essentially the same conclusion reached by former Prime Minister Yitzhak Rabin.
Hence withdrawal from Gaza has been Mr Sharon's defining policy as prime minister.
As a vehicle for this policy, Mr Sharon has formed a new party, Kadima.
Polls have consistently suggested that he will win the general election in March.
Growing unrest in the Palestinian territories is cause for alarm
Though he has been cagey about declaring exactly what his next move will be,
Mr Sharon is expected to push through a second major unilateral withdrawal from the West Bank.
This is what many Israeli voters have been expecting from him.
But without Mr Sharon, this further disengagement plan will not be possible.
It is his force of personality and political know-how that carried the Gaza disengagement plan through against very strong opposition.
Withdrawal from the West Bank was always going to be much more difficult.
If Mr Sharon does not contest the general election in March, it is possible that the party he abandoned, Likud, will form the next government.
Under the leadership of Binyamin Netanyahu, the party will halt the disengagement process entirely.
Mr Sharon had hoped that his political legacy would be to have gained international recognition for the borders of his country defined on Israel's terms. This seems impossible now.
Watching from the sidelines
The main problem the Palestinians have had with Mr Sharon's disengagement policy has been that they have not been consulted.
If Netanyahu came to power, policy would change significantly
They also fear his plans for East Jerusalem and its West Bank hinterland.
But among Palestinians, there is growing political chaos and the militant Islamic Hamas organisation looks like it will emerge from elections as a major political player in the Palestinian Authority.
For the international community, and the Arab states that have signed peace agreements with Israel, the combination of political chaos in the Palestinian territories and an Israeli leader without a plan of any kind, must be deeply alarming.