Hamas is trying to change the rules of the game on the Gaza border after reviewing events in the area over the past two weeks, Israeli officials say. The escalation on the border will not necessarily lead to a large operation by the Israel Defense Forces like Operation Cast Lead. In any case, the days ahead will clarify whether Israel can defuse tensions on the border and restore deterrence levels that had remained intact since the end of Cast Lead in January 2009.

Israel intends to compel Hamas to return to the state of affairs after the Gaza offensive in which the Islamic organization restrained its military wing and urged other Palestinian groups to refrain from operations against Israel. In the absence of a channel of communications, messages between Israel and Hamas are expressed mainly via displays of strength. Skirmishes are likely to continue in the days ahead. The skirmishes are fraught with danger.

The landing of a rocket on Tuesday near a kibbutz preschool close to Ashkelon was a reminder that an incident in which a weapon lands a few meters to one side or another could spark a conflagration. Had the rocket killed people, rather than cause light injuries, circumstances on the Gaza border today would be very different.

The escalation has been expressed in recent days mainly by Palestinian attacks against IDF patrols on both sides of the electric fence, and by increased firing of mortars and Qassam rockets. For the first time in many months, Hamas is playing a limited role in these attacks.

The main change, however, involves the encouragement the organization is giving indirectly to actions by other Palestinian groups, including rocket fire. These are relatively limited attacks. This year, some 180 rockets and mortar shells have landed in Israel (more than 200 shells and rockets landed by accident in Gaza ). By comparison, in 2008, a year that ended with Cast Lead, more than 4,000 rockets were fired at Israel.

Why has this minor escalation occurred now? It appears that Hamas is testing Israeli responses and wants to carve out space to operate and attack without instigating a major confrontation. Hamas' political chiefs have succumbed to pressure from the organization's military leaders, who want to blow off some steam via actions against Israel. Hamas also believes that the IDF has a harder time operating against missile launchers during the winter.

Hamas tried to clarify on Tuesday that the organization does not want to escalate attacks on Israel. Some of the groups that took part in mortar shelling and rocket fire against Israel over the past 48 hours are thought to be loyal to Hamas. However, the missile fired yesterday morning at Ashkelon was apparently the work of the so-called Army of Islam that operates semi-independently in the Gaza Strip.

In Gaza, commentators predicted that Hamas would work to calm things down to preserve the status quo and not be dragged into a dangerous military adventure. They point to Palestinian groups' measured response to the killing of five militants by an Israel Air Force bombing at the end of last year. Gaza sources say that small organizations took part in rocket attacks against Israel in recent days.

For its part, Hamas followed its routine procedure of evacuating some of its commanders and fighters. No major change or movement of forces was apparent on Gaza streets yesterday. Pedestrians and cars moved about as on any ordinary day. The people, who have grown accustomed to IAF bombings of Hamas installations and Islamic organizations' attacks on Israel, did not show signs of panic.

In the meantime, Chief of Staff Gabi Ashkenazi disclosed on Tuesday that Palestinians fired an advanced Kornet missile at an Israeli tank in Gaza two weeks ago. Details remained under wraps under orders from the military censor until Ashkenazi referred to the incident yesterday. Up to now, the Kornet has been used by Hezbollah and Syria's army.

The Kornet's debut in Gaza reflects an improvement in the enemy's military capability. In addition to the improvement of anti-tank weapons, medium-range rockets have streamed into Gaza; they threaten Tel Aviv. In light of such developments, IDF officials indicated yesterday that should events spin out of control in Gaza, Israeli forces would not have an easy time facing new challenges.