Gaza's deeply entrenched Hamas rulers won't be easily toppled, even by Israel's unprecedented bombings Saturday that killed more than 200 people, most of them men in Hamas uniform. For now, Israel's defense minister says he's striving for a lesser, temporary objective – to deliver such a punishing blow to Hamas that they will halt rocket attacks on Israel. But Israel's offensive, launched just six weeks before a general election in the Jewish state, is fraught with risks. The horrific TV images of dead and wounded Gazans are inflaming Arab public opinion, embarrassing moderate Arab regimes and weakening Hamas' rival, Palestinian President Mahmoud Abbas. Israel also risks opening new fronts, including unrest that could destabilize the Abbas-ruled West Bank and possible rocket attacks by Lebanese Hezbollah guerrillas on northern Israel. Hezbollah already proved its military prowess in its 2006 war with Israel, firing thousands of rockets. That war erupted while Israel was fighting in Gaza. Meanwhile, stone-throwing protests erupted across the West Bank on Saturday. Far from being cowed, Hamas leaders sounded defiant Saturday, and Hamas militants fired dozens of rockets into Israel. One Israeli was killed Saturday, and mounting Israeli casualties could turn Israeli public opinion against the offensive. “Once you set the ball rolling, you cannot determine where it is going to stop,” said Mouin Rabbani, a Jordan-based Mideast analyst. Israeli leaders say they had no choice but to act. A truce between Israel and Hamas, which took effect in June, began unraveling in early November, following an Israeli cross-border raid in Gaza. Since then, Gaza militants have fired scores of rockets. Israel held off on a major response, apparently in hopes that a new truce could be negotiated. The government, a coalition of the centrist Kadima Party and the center-left Labor of Defense Minister Ehud Barak, could not afford to be seen as indecisive, at a time when hardline opposition leader Benjamin Netanyahu was mounting a strong political challenge. Elections are scheduled on Feb. 10. Saturday's strikes appeared aimed at hurting Hamas, while minimizing risk to Israeli forces. Barak said the offensive would continue as long as necessary and could be widened – an apparent reference to sending in ground troops if necessary. However, Barak defined a narrow objective, to halt the rocket fire from Gaza, not to bring down Hamas. Eighteen months after seizing Gaza by force, Hamas is in firm control and commands thousands of armed men. It is unlikely to be brought down by force, short of Israel reoccupying the territory. Israel doesn't like that option because it doesn't want to get bogged down in urban warfare. “Israel is not looking for a knockout against Hamas because the costs are too high,” said Shlomo Brom, a former senior Israeli military official. “The purpose is to eventually return to a cease-fire.” While far from being defeated, Hamas took a hit Saturday. Hamas officials said all of the group's security compounds were struck. The militants may eventually have to agree to a truce, perhaps even on lesser terms than the June cease-fire, just in order to rebuild. However, the Gaza offensive also hurt Abbas, increasingly sidelined as a leader even before Saturday's violence. The past year of peace talks with Israel has had no visible results. Meanwhile, Hamas announced it will no longer recognize Abbas as president after his four-year term ends next month. Abbas could not be seen Saturday as openly siding with Israel. Abbas, who was in Saudi Arabia on Saturday, was to return to the West Bank on Sunday. But he did little more than call for restraint, and his security forces clamped down on West Bank protests against Israel's Gaza offensive, for fear they could spin out of control. “One of the victims (of the Gaza offensive) is President Abbas and the Palestinian Authority,” said Palestinian analyst Ghassan Khatib.