Israel's latest campaign in Gaza, which began on Wednesday with the killing of Hamas' military commander, Ahmed Jabari, and air strikes on the group's long-range rocket launchers, is a gamble -- and one that Israel might lose. Its goal is to compel Hamas to stop shooting rockets into Israel from the Gaza Strip and to crack down on other groups who are also doing so. Hamas, however, will find it hard to bend to Israeli pressure. In turn, it will be up to outside states, particularly Egypt, to foster a deal to end the fighting.

After Operation Cast Lead, the Israeli incursion into Gaza in 2008-2009 that resulted in over 1,000 Palestinian deaths and tremendous destruction, relations between Hamas and Israel wavered uneasily between hostility and tacit cooperation. True, Hamas' rhetoric toward Israel remained hostile, but the number of rockets that went over the border plunged and most of them were launched not by Hamas, but by more radical groups such as Palestinian Islamic Jihad. Hamas feared that launching large numbers of rockets would prompt Israel to again retaliate harshly and devastate Gaza, thus jeopardizing Hamas' political position there. At times, the group even tried to restrain its uncomfortable bedfellows. Indeed, although Hamas and Israel would both deny it, their interests were often aligned. As Aluf Benn, one of Israel's leading analysts, put it after Jabari's death, "Ahmed Jabari was a subcontractor, in charge of maintaining Israel's security in Gaza."

But Jabari's first allegiance, of course, was to Hamas. And, over time, Hamas became increasingly accepting of attacks on Israel. As the memory of Cast Lead faded, the number of attacks coming from Gaza began to rise once more. Israel claims that over 200 rockets struck the country in 2010. The number climbed to over 600 in 2011. And 2012 has seen even more -- over 800 before the current operation began. Most of these attacks came from other Palestinian groups, but more recently Hamas seemed to take a more active role in the violence, openly tolerating other groups' gambits and carrying out some strikes itself.

By this week, those attacks had "made normal life impossible for over one million Israelis," as Israeli Prime Minister Benjamin Netanyahu explained on Thursday. And so he and his government are again pounding Hamas in an attempt to restore the post-Cast Lead status quo, in which Hamas polices both itself and the rest of the strip. So far, Operation Pillar of Defense, as Israel calls it, has resulted in the deaths of 18 Palestinians (of whom roughly half were civilians). Hamas' response has killed three Israelis.

No single attack forced Israel to respond. In theory, it could have chosen not to. But the steady increase in rocket fire over the last few years had become politically intolerable for the Netanyahu government. With national elections approaching in January, his administration seemed unable to carry out perhaps government's most basic function: protecting citizens from violence. In addition, although Israel's political and security leaders might recognize the difference, ordinary Israelis simply did not care whether Hamas launched attacks itself or simply did not stop others from doing so. In other words, it was time to take out Hamas or else risk being taken out of office.

By launching this operation, Israel has resorted to its time-honored strategy of holding the government (or in Hamas' case, de facto government) that hosts militants responsible for the actions of the militants themselves. The approach has had some successes: in Jordan in 1970, Israel pressured Amman to instigate a bloody civil war against the country's Palestinian militants, eventually crushing them. But in Lebanon later in the same decade, Israel tried the same thing, with much worse results. The Lebanese government was too weak to crack down on terrorist activity in its borders and the country descended into chaos. In 2006, the same logic drove Israel's war against Hezbollah in Lebanon. Although the war was initially seen widely as a Hezbollah victory, Israelis now see it as a win. The Israeli military performed poorly, but Hezbollah has grudgingly kept the peace since then, fearing that rocket attacks from Lebanon would again lead to a devastating Israeli response. Indeed, the last six years have been the quietest along the Lebanon-Israel border in decades.

Israel's usual strategy might not bring about such decisive results this time. Hamas will find it hard to pull itself back from the brink and start stopping others' rocket fire. Jabari's death has infuriated Hamas' military wing, and whoever replaces him will be just as militant, if not more. Such a leader will press for revenge and warn Hamas' governing arm that his troops might well join rival groups if Hamas throws in the towel. After all, Hamas is trying to be both a resistance movement and a government. In many ways, it has succeeded as a government, establishing law and order and delivering basic services in Gaza. But Hamas must take care not to lose credibility among Palestinians for its willingness to fight -- and die -- in the struggle against Israel. So Hamas has tried to walk a fine line by allowing some attacks -- and, at times, even participating in them -- to maintain its militant street cred while shying away from an all-out assault that would push Israel to repeat Cast Lead.

Complicating the Israel-Hamas dynamic is the Arab Spring, particularly the fall of President Hosni Mubarak and the rise of Egypt's Muslim Brotherhood-led government. During the Mubarak era, Egypt helped Israel contain Hamas, maintaining a blockade on goods from Gaza and a travel ban on Gazans as well as supporting Hamas' rival, Fatah. During crises, Cairo often worked with Israel to press Hamas to back off. Today, however, Hamas has an ideological affinity with, and personal ties to, to the government of Egypt's new president, Mohammad Morsi. Meanwhile, the Muslim Brotherhood wants to court the Egyptian public, which is viscerally anti-Israel and highly supportive of Hamas. Openly siding with Israel in this conflict would be political suicide for Morsi. So, not surprisingly, Egypt has recalled its ambassador from Israel and publicly criticized Israel.

Israel, too, cannot afford to alienate Egypt. Putting aside the vital 1979 Egyptian-Israeli peace treaty (which still seems likely to hold), Jerusalem needs Cairo to keep whatever little pressure it can on Hamas. Although the rhetoric between the Morsi government and Hamas is far warmer than it was under Mubarak, the new government in Cairo has still not rushed to open up the Rafah border crossing with Gaza. In addition, Israel needs the Egyptian government to continue, and ideally expand, its recent crackdown on radicals in the Sinai, who have repeatedly attacked Israel. Finally, Israel needs the Egyptian government to refrain from whipping up pro-Hamas sentiment among its own people, which could quickly spread across the region and further destabilize already vulnerable countries like Jordan.

Israel also lacks any easy option to escalate if Hamas does not restrain itself soon. Although Israel has called up reservists and threatened to expand the scope of its military campaign if Hamas doesn't end the rocket attacks, Israelis do not want to reoccupy Gaza. What is more, the Obama administration would be unlikely to get behind a massive operation, since it would further complicate already tense U.S. relations with Egypt and other Arab countries. Perhaps most important, Israel's view of itself would be in danger. The western way of war stresses proportionality, which, in Gaza, means that Israel must limit its strikes--particularly on infrastructure and other targets that directly affect civilians. The logic of deterrence, by contrast, stresses disproportionate punishment: the enemy must suffer.

In the short run, the United States should press the Morsi government to broker a deal: a development that would not only end the current crisis but also indicate that Morsi can be a responsible leader who can work with Washington. In the long run, the United States, and the world, needs to make the choice between resistance and governance sharper for Hamas. There must be more and real rewards if Hamas moves toward becoming a regular government that eschews violence. Allowing more normal economic activity and more people to go to and from Gaza would show Hamas that the world will let it govern Gaza. At the same time, there must be serious and sustained punishment for any continued rocket attacks or other violence with the international community maintaining economic pressure on Hamas and accepting that Israel will hit Hamas hard to keep its deterrence credible. But Cast Lead showed that any military campaign, no matter how devastating, can only deter Israel's enemies for so long. Israel and the international community need to take some bold political risks in trying to bring Hamas into the fold -- or else start preparing for the next war.