The rocket barrages against communities inside Israel and the Israel Defense Forces operations in the Gaza Strip that have left at least 16 Palestinians dead over the past three days all point in one direction: Following many weeks of being kept on ice, the likelihood of a major military operation in the Gaza Strip is once more at the forefront.

In recent months it seemed that the major IDF operation (which had been discussed sporadically for about a year and a half) had been dropped from the agenda. There were a number of reasons for this.

Firstly, the political leadership found it difficult to accept that the operational plans produced by the IDF were realistic. The concerns that a major ground operation would have limited gains against Hamas and would cost the IDF many casualties, in parallel with an inability to plan for a scenario that would restore relative calm in the Strip, raised many reservations in Jerusalem.

Playing a role in the background, meanwhile, was the paralysis that took hold of the political leadership as the release of the final Winograd Report loomed. So long as there was a question mark hanging over the Olmert government, there was a reluctance to make any decisions concerning an operation in the Strip.

However, the apparent change in recent weeks does not only stem from the fact that the prime minister has managed to survive the Winograd trial. It is mainly linked to developments along the border between the Strip and Egypt, which have added a new element of instability to the already complex situation. Egypt may have announced this week that it has resealed the Philadelphi Route at Rafah, but it is doubtful whether this is a hermetic closure.

The Hamas operation which brought down the wall greatly impressed the IDF. An officer who held a senior post in the past in Southern Command said Thursday that he had told his Palestinian Authority counterparts at the time, security officials loyal to Mahmoud Abbas, that the wall would stand for many years after the disengagement. His assessment, he admits, was mistaken. What Hamas managed to achieve is a fundamental change in the situation in the area.

Why would the breach in the wall expedite an Israeli operation? Because the absence of stability contributes to escalation and the loss of control. The action has bolstered the confidence of Hamas' military wing. This operational success may lead them to take more risks.

On Wednesday, the Hamas representative in Tehran threatened Israel with a wave of suicide bombings inside the country. To this must be added the situation in Rafah. While smuggling had previously been rampant, the absence of any border controls in recent weeks appears to have enabled Hamas to intensify its effort to bolster its arsenal. At the same time, terrorist organizations have managed to send a number of teams into Sinai, with the aim of carrying out attacks in Israel. Without a wall, Egypt's ability to seal the border against the terror cells is limited.

In light of these developments, it is once more possible to hear Defense Minister Ehud Barak talk about his desire to avoid a major operation, but at the same time that such a step may be inevitable. The current steps being taken - continuing the economic blockade, which has been broken by Hamas; limiting the amount of electricity being supplied; limited ground operations ¬ are all considered essential before a final decision on embarking on a massive operation.

What would a massive operation include? Israel faces three main challenges in the Strip, each of which is concentrated in a different geographic location: the Qassam attacks against Ashkelon and Sderot (northern Strip); the strengthening of the terrorist groups in Rafah ¬ (where the smuggling takes place); and the Hamas regime (Gaza City).

It is fair to assume that for the latter, the IDF will opt to deal with the regime from a distance - relying on an air operation. A ground operation would include a combination of sorts for dealing with the first two problems. If it turns out that Philadelphi Route remains entirely breached, this may be an incentive for a ground operation toward Rafah. However that introduces a separate dilemma: An operation close to the border with Egypt may lead to friction with Cairo.

In cabinet discussions, senior IDF officers have made it clear that they need time in such an operation. They stressed that there is no point in carrying out a major initiative if they are not allowed to carry out the necessary search and destroy missions and arrests in the areas the army will bring under its control, following the initial offensive. Another critical element will be the weather, which is likely to delay a major operation for at least a month.

Meanwhile, the combative attitude adopted by Cairo recently in its statements against Hamas is further exacerbating relations between the two sides. Egyptian Foreign Minister Ahmed Abul Gheit warned yesterday that Egypt would "break the legs" of Palestinians who try to enter Sinai ¬ a statement that sounded almost like a declaration of war.