Israeli Deputy Prime Minister Ehud Olmert on Monday defended the dismantling of Jewish settlements in the Gaza Strip, saying that the government's plan would move forward despite opposition from members of the ruling Likud Party.

"This in my mind is the right thing to do, the only thing to do," Olmert told a meeting of Washington Post reporters and editors.

Olmert acknowledged that only 40 percent of Likud members had supported the Gaza pullout in a referendum. But he said that Prime Minister Ariel Sharon was determined to proceed. "He will do everything in his power," Olmert said. "There is no other alternative."

A party veteran, Olmert said he was not concerned about the potential political fallout from disregarding the majority view. "My understanding of leadership is doing what should be done," he said. "I am not starting my career now."

Olmert acknowledged that the Gaza withdrawal would cause emotional trauma for uprooted families. He also said that some older Israelis may be facing dislocation for a second time, since some people now in Gaza had to move from outposts and settlements in the Sinai after a peace treaty was signed with Egypt in 1979.

But the deputy prime minister said things had changed, pointing out that support by even 40 percent of Likud members for the voluntary closure of settlements would have been unthinkable as recently as two years ago. "Now it has happened. . . . So, there is a certain change," Olmert said.

"This is not the comprehensive solution, but it would be the setting of a historic precedent that is so attractive," he said.

Olmert also discussed the Gaza withdrawal in the broader context of the confrontation between Israel and the Palestinians. Palestinians must realize that Israel would be unlikely to withdraw to the borders defined after the 1967 Middle East war, he said.

Though he said there were certain things Israel could not give up, Olmert warned that daily confrontations between the Israeli army and Palestinian civilians in the West Bank were doing Israel no good.

"I think it destroys our reputation," he said. "The perception of occupation and the lack of political and some civic rights [for Palestinians] is killing us."

Olmert made these remarks during a week in which Israeli troops launched a major operation in the Rafah refugee camp in southern Gaza, using armored vehicles and bulldozers. Yesterday Palestinian hospital officials reported 19 Palestinians killed in the Gaza Strip and 62 injured. The United Nations and the European Union both demanded a halt to the Israeli operation, and Arab countries called for an emergency meeting of the U.N. Security Council.

Olivier Roy, a French scholar of Islam, said this week that secular society is winning out over theocratic government in the Muslim world.

"Political Islam, in the sense that I define it, as establishing an Islamic state in a given country, is losing out," said Roy, a senior researcher at the National Center for Scientific Research in Paris.

One key example, he said during a meeting at The Washington Post, was Iran, which he described as having evolved into one of the more secular societies in the Middle East because people were disillusioned with religion as a basis for government. "Iran went to the end of the trail, and it did not work," he said.

The Islamic movement has integrated itself into mainstream politics in many other countries as well, he said. What is seen now, he added, is a trend toward the privatization of Islam, in madrassas, or religious schools.

"This does not mean there is less Islamicization, just a gradual separation between politics and Islam," he said. There is more of an emphasis on Islam in everyday life, rather than as an ideology, he said.

Pakistan and Saudi Arabia are different, however, Roy pointed out. In both countries, he said, Islam is at the heart of government.

Islam is undergoing what he called a "deterritorialization" that is no longer country-specific, he added. He said that one phenomenon tends to be discounted in analysis of the impact of Islam: the fact that the religion inspires many converts. He cited fighters in Chechnya and Afghanistan who were recruited as Muslims, not because they were interested in a particular nationalist or secular agenda or identity.

There are also converts who settle in non-Muslim countries. "Disconnection is a permanent factor," Roy said of such Muslims. Some groups are satisfied living, for example, in southern Europe, in countries bordering on Muslim countries. "Even if they issue communiques about Palestinians, [those people] will remain in the West," Roy said.