Israel is seeking deterrence. It has no intention of liquidating the Hamas terrorist infrastructure in the Gaza Strip nor of wiping out its leadership. The government's goal for the defense establishment is to create a deterrence that will halt any attacks from the Gaza Strip on Israeli towns, villages and farming communities. Creating deterrence requires that the other side truly believe the threats that are being made. IDF generals consistently say Israel has never made any military threat it has no intention of carrying out, if ordered. This was the case concerning numerous alerts along the Lebanon border since Israel pulled out and this is the case now with the Palestinians. There is a lot of bluffing and posing, but a heavy-handed Israeli air, land and artillery assault on terrorists is certainly an option no doubt about it. The IDF has amassed armor along the border and, for the first time, has deployed artillery, which would definitely mark a major change in tactics if used. Psychological warfare was also employed by dropping anti-Hamas leaflets in the Gaza Strip as fighter jets broke the sound barrier in a further expression that the times were changing. But military sources said that, for now, the reaction to the heavy Kassam rocket strikes will be limited to pinpoint strikes against specific targets and a renewal of targeted assassinations. The reactions won't be limited to the Gaza Strip, though. Arrests will continue in the West Bank. Clamping a closure on the West Bank and Gaza is not punishment but rather a security precaution to prevent bombers from getting in. Israel's reaction now is crucial because it will set the pattern for the future. Israel has said the rules of the game are different now, just like it did with Hizbullah when it pulled out of Lebanon five years ago. The latest Kassam barrages were not unexpected. It was a script known ahead of time only the timing was uncertain. Now the new rules are being tested. Israel wants to extract a price for this unprovoked attack. In the Middle East, deterrence is a difficult thing to measure. The deterrence in the mind of one country that is extremely vulnerable to civilian casualties cannot be measured on the same level as a people whose leaders have different regard for human life. To save lives, Israel must act with great ferocity. Additionally, more is at stake here than deterrence vis- -vis the Palestinians. If the IDF does not deliver a firm message that the rules have really changed, it could have grave ramifications in the north with Hizbullah, not to mention across the region.