There is an enormous gap between the reasons Israel is giving for the decision to impose significant sanctions against Hamas rule in the Gaza Strip, and the real intentions behind them. Defense Minister Ehud Barak authorized Thursday a plan for disrupting electricity supply to the Gaza Strip, as well as significantly shrinking fuel shipments. This is supposed to reduce the number of Qassam rocket attacks against Sderot and the other border communities. In practice, defense officials believe that the Palestinian militants will intensify their attacks in response to the sanctions.

As such, the real aim of this effort is twofold: to attempt a new form of "escalation" as a response to aggression from Gaza, before Israel embarks on a major military operation there; and to prepare the ground for a more clear-cut isolation of the Gaza Strip - limiting to an absolute minimum Israel's obligation toward the Palestinians there.

Several weeks ago, Barak said Israel "is getting closer" to a major operation in the strip. Like Prime Minister Ehud Olmert and Chief of Staff Gabi Ashkenazi, Barak is not excited about this possibility. He knows that it will not be easy, and there are no guarantees for positive results. Many soldiers will be killed and so will many innocent Palestinians, because the IDF will employ a massive artillery bombardment before it sends infantry into the crowded built-up areas. This will be a "dirty war," very aggressive, that will have scenes of destruction similar to southern Lebanon in 2006. The sole exception: unlike in Lebanon, the population there has nowhere to run.

Moreover, Ashkenazi has told the cabinet that he will only support an offensive operation if it is long-lasting. If after several weeks of fighting, the IDF is allowed time to carry out arrests and gather intelligence, then the chief of staff sees a point for the operation.

Defense sources say the sanctions will lead the militants to intensify their attacks to show that they do not succumb to Israeli pressure. And because the sanctions will not be severe - so as not to create a humanitarian crisis - they will not be effective. It is actually expected that the gasoline shortage will have a greater effect than the disruptions in the electricity supply - which normally happens because of equipment breakdowns.

The decision on sanctions is also an attempt to give expression to the inclination to completely disengage from Gaza. In this way Israel is sending a message to the Palestinian leadership in the strip that it must seek alternatives, however minor, to goods and services coming from Israel. This touches on the day after the Annapolis summit. Failure at the summit may lead Palestinian Authority Chairman Mahmoud Abbas into the arms of Hamas. In such a case, Israel is raising a big stop sign at the exit from Ramallah: Passage to Gaza is closed.