Embittered by what they feel is betrayal by their government and troubled by the uncertainty of their future, militant Jewish settlers in this desert community have vowed to blockade the only road linking Israel and Egypt and wreck the peace treaty before the last third of the Sinai is returned to Egypt in 17 months.

The resistance movement represents only a small minority of the 3,500 settlers who have moved to the Sinai Peninsula since Israel captured it from the Egyptians in the 1967 Six-Day War. Most have become resigned to moving and are concerned mostly about how much compensation they can extract from the government in Jerusalem.

But the holdouts' determination approaches fanaticism. Many are armed, which presents a nightmarish delemma to the govenment of Prime Minister Menachem Begin.

If he fails to forcibly remove the settlers, he could undermine normalization of relations with Egypt, the major accomplishment of his first term of office. But if he does force them out, he faces in an election year the grisly specter of Jews fighting Jews on land that many Israelis regard as part of the Jewish biblical legacy.

"Today Yamit, tomorrow Jerusalem. This is where we make our stand," Rabbi Yisrael Ariel, spiritual leader of a group called MAOZ, said in an interview. "We are not going to wait until they take us out of here in 1982."

MAOZ, an acronym of the Hebrew words for "struggle, initiative an identity," is the nucleus of several resistance movements that have been forming in this seaside development town and the 13 surrounding agricultural settlements, all of which are scheduled to be closed after the current school year ends in June.

Ariel, head of a Jewish seminary here, would not discuss details of his group's sistance plans, saying they are being held secret for the tactical advantage of surprise.

"But we will bring her thousands of people, who are already organizing to demonstrate. We know the places. We are just waiting for the exact time," said Ariel, who said MAOZ has 60 families involved in the effort.

Another MAOZ leader, Avi Farhan, a 33-year-old native Israeli who was carrying a .38-caliber revolver in his waistband, also spoke of "measures we can't publicize." But he vowed, "We are not leaving Yamit peacefully, I can assure you of that."

The opening salvo in the struggle could come as soon as Nov. 25, the deadline set by a group of settlement farmers for the government to come to terms with their demands for compensation.

The farmers say they are willing to leave the Sinai if offered enough money to underwrite comparable enterprises in Isael. But they insist that if Begin refuses to meet with them when he returns from his visit to the United States, they will cut the Sinai coastal road to all traffic.

Shaoul Sela, who owns a house and 20 acres of tomato crops in the Moshav Sedot agricultural cooperative across the road from Yamit, said the demonstrations could lead to serious tensions between Israel and Egypt and ruin normalization of relations between the two countries.

"All it takes is one stone thrown at an Egyptian diplomat in his car. We will cut the road with tractors, trucks, and everything we have. We have lots of equipment, and nothing will move on that road for weeks," Sela said.

The settlers offered a preview of the disruption last year, protesting the turnover of the central Sinai, which including the nearby Arab town of El Arish. Scores of flatbed trucks and tractors were driven onto the highway and left there in a hopelessly entagled jumble of equipment, as the farmers walked away with their ignition keys. Some erected makeshift barriers and burned tires.

Similarly, farmers in the now-closed Neot Sinai settlement battled with Israeli troops, throwing containers of burning fuel and inflicting serious injuries on some soldiers.

Sela and many other farmers here say they hope it will not come to that again. But they say they have become embittered and depressed because the government is not offering then nearly enough to resettle elsewhere.

Last Sunday, the Israeli Cabinet approved in principal a plan in which most of the farmers would receive about $215,000 for their farms and houses. According to Sela, however, Israel's rampant inflation has driven property values to such exhorbitant levels that a minimum of $300,000 would be needed to start a modest agricultural enterprise.

The depression has become so widespread and severe that a team of psychiatrists was brought in for consultation, marriages have broken up, two women have tried to commit suicide and many farmers have begun to drink heavily, the settlers say.

The farmers are particularly torn, they say, because when they moved here with the puoneering spirit of Zionism, they had to toil ceaselessly and invest all their money into converting the land from sand dunes to productive soil.

"This isn't soil; it's sand. And any money I've made I've had to invest back into it for equipment, water and other things. Why should I bother to put more money into it now, when it is going to be given to the Egyptians?" Sela asked.

"People are becoming very bitter. More and more of them are becoming fanatic as the deadline gets closer. The land we're talking about is a fraction of the Sinai. Why can't Israel keep it? Egypt isn't going to go to war over some tomatoes. People fight wars over oil, not tomatoes."

Max Dector, and insurance agent who came to Yamit four years ago, represents a more passive viewpoint -- unquestionably held by the majority of residents here.

Waving his hand toward the broad expanse of palm-lined beach on the edge of bright blue Mediterranean Sea, Dector said, "People who came to Yamit came to heaven on earth -- Shangri La. Suddenly it is all taken away. I can understand those who say they will refuse to leave under any circumstances, but I am not one of them."

Dector sold his apartment for $30,000 more than he paid for it, and the government has offered residents a year's wages for each year spent here, an offer Dector believes is fair.

But beyond that, he thinks peace is worth any price.

"I have one son who has been through two wars. I don't want him to go through another," he said. "I don't want my son to go through another war because I wouldn't move out of Yamit for the sake of peace.

"I decided to stay here until the last half hour before the deadline, and then repaint my flat and put up a sign saying, 'Anybody who comes here, may they be as happy as I have been.'"