JERUSALEM – Israel has dropped tons of bombs on the Gaza Strip in an unprecedented show of force to make Hamas stop rocket attacks, but it has not said it will try to topple the Islamic militants who have ruled the territory for 18 months.
Such a limited definition of goals gives Israel considerable flexibility in deciding when to end the assault, especially if international pressure mounts, while still calling it a success. But this guarded approach also offers Hamas good survival odds, even if the onslaught leaves it badly weakened.
Israel's unwillingness to reoccupy Gaza or openly try to install a new ruler there gives Hamas considerable leverage in future cease-fire negotiations.
In exchange for calm on Israel's border, Hamas demands an end to the crippling blockade imposed by Israel and Egypt after the Hamas takeover of Gaza 18 months ago. Hamas, which won 2006 parliamentary elections, seized control after a power-sharing agreement with the rival Fatah movement collapsed in violence.
Ending the blockade could help Hamas recover quickly and prolong its rule indefinitely. That, in turn, would all but destroy prospects of an Israeli-Palestinian peace deal.
Israel has been negotiating for the past year with Hamas' rival, moderate Palestinian President Mahmoud Abbas, who controls the West Bank. However, Israel says it cannot implement an agreement as long as the Iranian-backed Hamas, sworn to Israel's destruction, controls half of what would be a Palestinian state.
With peace talks producing no tangible results, a weakened Abbas may not be able to cling to power much longer if Hamas remains in control of Gaza. Abbas' opponents claim his term ends on Jan. 9 and have said they will not recognize his authority after that.
Abbas seemed increasingly irrelevant this week, voicing little more than tepid condemnations after the Israeli offensive began. On Monday, Hamas quickly rebuffed his offer to serve as a broker between Israel and the Islamists.
The previous cease-fire between Israel and Hamas, brokered by Egypt, took effect in June.
Its terms were never made public, but Hamas says the understanding was that Israel would gradually ease the blockade.
Instead, Israel allowed in only limited supplies, and it repeatedly closed border crossings for sporadic rocket fire on Israeli border communities. With Israel controlling all of Gaza's cargo passages, the closures have led to widespread shortages of basic goods.
Hamas, meanwhile, kept bringing in weapons through smuggling tunnels in preparation for the next round of fighting.
Ahmed Yousef, a Hamas leader, said Monday that the movement will not agree to a new truce without an end to the blockade. "Israel wants calm in return for a slow death (of Gaza)," he said. "The calm can only be restored if the siege is lifted."
Previous military offensives have never been able to stop the rockets. Throughout the latest offensive, Hamas has managed to continue firing the crude weapons, killing three Israelis and reaching farther into Israel than ever before.
Israeli Defense Minister Ehud Barak has been vague in defining his objectives. On Monday, he told a special session of parliament that "we set out to deal Hamas a severe blow, a blow that will cause it to stop its hostile actions from Gaza at Israeli civilians and soldiers."
Such caution may be a lesson learned from the 2006 war against Lebanese Hezbollah guerrillas, in which Israeli Prime Minister Ehud Olmert set out the ambitious goal at the outset of destroying Hezbollah. Olmert's haste, and Israel's failure to accomplish that goal, contributed to the postwar backlash against him and the general sense in Israel that it lost the war.
Barak and his coalition ally, Foreign Minister Tzipi Livni, have been evasive about whether Israel would try to topple Hamas. Livni has spoken only of creating a "new reality" along the Gaza-Israeli border. On Sunday, she declared that Israel does not want to reoccupy Gaza — a step that would almost certainly be required to oust Hamas and its 20,000-strong army.
It's not clear to what extent Israel's upcoming general election, set for Feb. 10, plays into the decision-making. Israeli officials deny there are any political motivations to the offensive. But Barak and Livni — who are competing to become prime minister — are under public pressure to look tough.
Israel also might be motivated to act before President-elect Barack Obama takes office. Some Israelis have expressed concern that Obama might not be as supportive as outgoing President George W. Bush.
Political rivals have sought hard to show an image of unity, but disagreements broke into the open Monday.
Olmert's closest ally, Vice Premier Haim Ramon, reiterated that Israel must bring down Hamas, arguing that anything short of that would simply set the stage for more fighting down the road. Ramon and others have not said who would run Gaza after a war to the finish.
Zakarya Sinwar, a history professor at Gaza's Islamic University, said that "Israel can destroy everything in Gaza, but will find no one to surrender politically." Instead, the embattled Hamas also appears to enjoy a new wave of sympathy, after months of declining popularity.
Eyal Ben-Reuven, a senior Israeli army commander in the Lebanon war, agreed that Hamas cannot be brought down by force. "Hamas is an ideology, and we cannot cancel out an ideology militarily," he said.
At best, he said, Israel can scare Hamas into halting rockets by exacting a high price, and then approach new truce talks from a position of strength.
Even within these parameters, he said, Israel may find itself sending in ground troops, but for a limited operation, to deliver Hamas a stronger message.
Karin Laub has covered the Israeli-Palestinian conflict since 1987.