Since Hamas' violent takeover of Gaza last June, a pattern of tit-for-tat provocation has defined the organization's relationship with Israel.

One side launches an attack, the other side responds with disproportionate or indiscriminate force. The period of escalation then tapers off until the next flare-up, which generally involves increased intensity, more civilian casualties and higher-grade weaponry.

This spiraling escalation has created a self-reinforcing logic, leading inexorably to a major Israeli operation in Gaza.

Hamas must answer - at least to the Palestinians in Gaza who primarily pay the price for this cycle of violence - as to why it continues to fire rockets into Israel when it is fully aware of the consequences.

Is this "resistance" for its own sake, without sense or strategy, or is there any coherent purpose at work? Hamas might be seeking to enhance its position in cease-fire talks, assert its supposed veto power over peace negotiations or divert attention from its failure to govern Gaza responsibly. No matter what drives these decisions, it has to anticipate and accurately assess the reaction of the Palestinian and Arab people who would be watching the bloody images aired on Al Jazeera and international news outlets in the wake of a devastating Israeli invasion.

Hamas may suppose that Israel does not have the stomach for another war so soon after Lebanon. Or it might hope for political benefits from an Israeli invasion of Gaza. Worst of all, Hamas could be driven by the agenda of its external sponsors.

The most important question that Hamas has to answer is whether any such objective would be worth the price in lives, misery and destruction that would be paid by the people of Gaza. The Palestinian people, especially in Gaza, are enduring unconscionable suffering. The policies of any responsible leadership must be aimed at easing rather than intensifying their plight. If Hamas is hoping to replicate Hezbollah's performance of two summers ago, it is badly misreading the Israeli and regional scene.

Israel seems locked on a path towards a new military offensive in Gaza. Any Israeli Prime Minister would be hard pressed to resist pressure from the public and political opponents for major action if rockets continue to hit towns in the Negev.

If Hamas is counting on Arab support in case of a military confrontation with Israel, it may be badly misinterpreting the political realities.

Hezbollah's assertion of political dominance in Lebanon has left many Arab states uncomfortable with the prospect of having two Iranian-sponsored regimes in the heart of the Levant.

A Hamas activist was quoted saying "What happened in Gaza in 2007 is an achievement; now it is happening in 2008 in Lebanon. It's going to happen in 2009 in Jordan and it's going to happen in 2010 in Egypt." Because of this attitude, Arab governments will be unlikely to wholeheartedly support Hamas - or encourage their publics to do so - in the event of an Israeli attack.

Israel also needs to step back and seriously consider the full implications. An ill-fated military action would result in massive civilian casualties, the destruction of what remains of Gaza's infrastructure, and a major backlash against Israel, the United States and those Palestinian and Arab leaders who continue to advocate peaceful negotiations.

Israel would have to be prepared to take the grave steps needed to achieve defined objectives, and just as important, have a real exit strategy. Such measures would produce a heavy toll in casualties among Israeli soldiers and immense death and destruction to Palestinian civilians.

Furthermore, a botched, massive incursion into Gaza would be politically reckless. Even if such an assault damaged Hamas' infrastructure and eliminated its leaders, it could still leave Hamas politically strengthened.

It is important and still possible to avoid a full-scale confrontation.

Hamas should avail itself of the ongoing Egyptian efforts to bring about a de-escalation, and end these reckless rocket attacks at once.

In its own interests, Israel should lift the siege of Gaza by handing over the Gaza crossing points to the Palestinian Authority with European monitors, and start allowing improvements in the quality of life in the West Bank. Hamas has to stop its opposition to this plan which would lift the siege of the long-suffering people of Gaza.

The bottom line is that a massive Israeli reaction to continued rocket attacks is predictable, even if it proves self-defeating. Hamas must therefore decide if it is sufficiently interested in protecting the civilian population of Gaza from the horrors of an Israeli invasion by agreeing to an Egyptian-brokered compromise.

Whatever it does, Hamas will not be able to parrot Hezbollah leader Hassan Nasrallah, who claimed after the 2006 debacle in Lebanon: "If I had known" that Hezbollah's actions "would lead to such a war, would I do it? I say no, absolutely not."

Ziad Asali is president of the American Task Force on Palestine.