Aharon Peretz has spent most of his 51 years in this cactus-fringed, working-class town, and he would like to stay.

But his wife and six children feel differently: Daily retreats to the basement during rocket strikes from the nearby Gaza Strip have frayed their nerves, and an attack that cost an uncle both his legs has convinced them it's time to go.

Peace will return for his family, Peretz has decided, only if Israel chooses to go to war with his neighbors.

"There is no other option," he said. "Israel must enter Gaza and deal seriously with those who are launching these Qassams," as the crude rockets are known.

That sentiment is gaining currency across Israel, and the political rhetoric is growing more bellicose. With each new barrage of rockets, the government comes under greater pressure to conduct a massive military operation that might improve conditions in Sderot, but could also entail heavy casualties on both sides and further undermine the already anemic U.S.-backed peace process.

The government has so far resisted the calls for a wider war beyond its present Gaza strategy of intense political pressure, a crushing economic embargo and frequent military strikes targeting those suspected of responsibility for the rockets. A full-scale invasion, officials say, could backfire and benefit Hamas, the armed Islamic movement that controls the territory. Israel also insists it does not want to be drawn back into Gaza less than three years after it withdrew its settlers and troops.

But Defense Minister Ehud Barak said this month that the military had been ordered to draw up plans for a ground assault in Gaza, and other top government officials have talked openly of toppling Hamas. Politicians on both the right and the left say that they expect a major operation and that all it will take to trigger one is for a Qassam to fall in the wrong place.

"Time is running out," said Defense Ministry spokesman Shlomo Dror. "One of these days, a Qassam will hit a bus, and then what do we do? Can the Israeli government stand against the people of Sderot?"

Still, Dror said, the cost of an invasion would be high. Gaza is one of the world's most densely populated places, with likely military targets scattered throughout civilian areas. The military estimates that in a full-scale invasion, about 100 Israeli soldiers and 1,000 Palestinians would die, he said.

The Qassams have made life difficult in Sderot, a desert town of 20,000, and other areas near the Gaza border. But so far, casualties have been limited.

By contrast, over the first two months of the year, Israeli military operations involving both ground troops and airstrikes have resulted in the deaths of 126 Palestinians, according to health officials in Gaza. The Israeli military says that in the past three months, 180 Palestinian fighters, as well as 13 civilians, have died during its operations.

"What's coming out of Gaza is not a strategic threat," said Shalom Harari, a former top Israeli military intelligence official. "It's terrible. It puts political pressure on the government. But it's not a strategic threat."

Harari is concerned it could soon become one, however, as Hamas gains military strength through support from Iran. That assistance could in time mean rockets with much longer range and far greater accuracy and lethality, he said. The government's critics on the right raise the same concern in arguing for the Israel Defense Forces to go into Gaza as soon as possible. The number of Israelis under threat from the rocket fire, they say, is bound to grow unless the military acts.

"Soon enough, they'll also threaten Tel Aviv if we do nothing to stop them," said Yuval Steinitz, a lawmaker from the Likud Party, which advocates a hard-line policy in dealing with the Palestinians.

Steinitz said the military would have to occupy Gaza for, at most, a few months. In that time, he said, Israeli forces could eliminate Hamas's weapon stockpiles, destroy the rocket launch sites and reassert control over the Egyptian border, where explosives are smuggled in. The casualties may be high, he said, but the operation would save lives in the long run.

"I'm not saying it will be easy. The world, at the beginning, might condemn us," Steinitz said. "But this is the only real solution. This war of attrition is not good for us. No state would tolerate daily rocket attacks on its soil."

There is no guarantee, however, that a major military operation would succeed in stopping the attacks. It could increase them. Military analysts and government officials also worry that Israeli troops would get stuck in Gaza, locked in urban warfare with a guerrilla force that has been preparing for just such a fight.

"You start this operation, and I don't know how you can end it," said Dror, the Defense Ministry spokesman.

Matti Steinberg, a former adviser on Palestinian affairs to Shin Bet, Israel's domestic security agency, said there is a far less costly way to stop the attacks: a cease-fire.

Without one, Steinberg said, Israel is on a path toward war, which could have disastrous consequences for the U.S.-backed peace process that began in Annapolis late last year. "The entire rationale of Annapolis would be doomed," he said.

An invasion, he said, would ultimately strengthen support for Hamas and undercut Palestinian Authority President Mahmoud Abbas, who leads the more secular Fatah movement.

Hamas spokesman Fawzi Barhoum agreed. He said the group was expecting a major Israeli offensive and warned that it would only lead to more armed resistance. "Any military operation against Gaza will not give security to the occupation," he said. "It will just increase the popularity of Hamas."

Israeli military sources said that much about the invasion plan remains undecided, including its exact timing, size and duration. The plan would also hinge on support from the United States and key nations in Europe, officials said.

Israel's Gaza policy has already drawn intense international criticism, particularly for its reliance on economic pressure, which U.N. and European Union observers have warned could lead to a humanitarian crisis.

Mark Regev, spokesman for Prime Minister Ehud Olmert, said Israel's response has been "proportionate and, within the confines of international law, what is considered justifiable self-defense."

But it has not stopped the rocket fire.

On Friday, thousands of Israelis demonstrated their solidarity with Sderot's residents by streaming into the city to shop. Despite the threat, the cloudless winter day took on a carnival-like atmosphere, with DJs spinning dance music and shoppers walking the streets seemingly unconcerned by the possibility of an attack.

"We don't have many days like this," said Michael Amsalam, 58, a town councilman. But he was not optimistic there would be many more.

When a nearby motorcyclist unexpectedly revved his engine, Amsalam flinched, then described what it was like to hear a rocket fall on his town, with nothing to do afterward but brace for the next one.

"Only the ones who live here know the feeling of the Qassam, the feeling of fear," he said.