Fortress Israel.

Byline: The Register-Guard

It's becoming increasingly clear that Israeli Prime Minister Ariel Sharon doesn't see any value in further pursuing peace negotiations with the Palestinians. More precisely, Sharon doesn't believe the Palestinians can provide a credible, trustworthy leader with whom to negotiate.

Viewed from that perspective, some of Sharon's more repugnant recent decisions - the assassination of Hamas founder Sheik Ahmed Yassin and the construction of a controversial security barrier to wall out the Palestinians - are, despite their cruelty, understandable.

Having abandoned any thought of negotiating, Sharon is focused totally on Israel's security. It doesn't matter if his recent actions are seen as setbacks to the prospects for peace because Sharon doesn't believe peace is possible, at least in the near future.

That could explain both the timing of the ill-advised Yassin assassination and the energy Sharon has invested in his controversial plan for a unilateral Israeli withdrawal of settlements in the Gaza Strip.

Evacuating Israelis from most or all of the Gaza Strip would solve significant security problems. The 21 Gaza settlements crammed into the narrow coastal strip alongside 1.3 million Palestinians are an expensive security burden to Israel. They also are a continuing provocation to impoverished Palestinians, who can't understand why these Jews are unwilling to live within the borders of their own country just a few miles away.

But Sharon was not about to cede Gaza to Hamas without making certain that his enemies would not be able to claim Israel's withdrawal represented a victory for terrorists. Suicide bombers, many trained by Hamas, have killed 377 Israelis and wounded more than 2,000 in the past 3 1/2 years.

And so Sharon signed Yassin's death warrant. With Yassin eliminated, Sharon can evacuate the 7,500 Israeli settlers in Gaza behind the fortified border he's building around Israel. He can encircle Jerusalem, annex key portions of the West Bank and hunker down.

Yassin's assassination also quiets Sharon's right-wing Likud critics and signals Israel's enemies that the withdrawal from Gaza will be nothing like the hasty retreat from Lebanon four years ago.

Absent any need to negotiate with Palestinians and without any concern for world opinion, Sharon apparently felt free last week to renew threats on the life of Yasir Arafat.

Sharon reportedly said that it was possible Israel could act at some point against Arafat, the Palestinian Authority leader, who has not left his besieged West Bank compound for nearly two years.

The deteriorating diplomatic environment in the Mideast does not appear to offer much hope in the short run for successful outside intervention.

But that shouldn't deter the Bush administration from using its upcoming meeting with Sharon to insist that Israel resume participation in the peace process.

Although no one can say with certainty what shape such a process might take, the alternative is unac- ceptable.