When the radical Islamist Hamas took over the Gaza Strip in June, several commentators concluded that since the organization's primary concern was consolidating its rule, it would try to reach a long-term truce with Israel. In accordance with this rationale, Hamas would be more flexible on a deal to free the abducted soldier, Gilad Schalit, and would refrain from attacking Israel. Neither scenario materialized. In reality, Hamas is not signaling moderation, but continuous violent struggle against the Jewish State. The organization is waging a limited war against Israel and preparing for an escalation in the conflict. Kassam rocket attacks have intensified, and work continues on extending the range of the rocket. Infiltration attempts by terrorists into Israel have also grown. Palestinian mortars have even targeted the crossing points into Gaza used for transferring much-needed food and fuel into the Strip. Additional tunnels have been dug, and arms smuggling has reached a peak since Hamas took control of Gaza. Furthermore, Hamas sends hundreds of its men to Iran for advanced training. And Hamas has significantly enhanced its military capabilities across a range of areas. WHILE ISRAEL has recently become slightly more active militarily in the Strip, it still shows unnecessary restraint. The fears that a large-scale ground attack in Gaza might be costly in casualties are exaggerated. It's an assumption which needs reassessment. Similar arguments were voiced against a large-scale invasion of Judea and Samaria before Operation Defensive Shield in 2002, and they were proven wrong. Gaza has yet to be subjected to an Operation Defensive Shield-like military treatment, and this is why the level of violence emanating from Gaza is so high. Moreover, delay in addressing the Hamas challenge might prove more costly in the future, as our experience with Hizbullah in Lebanon has clearly shown. STRATEGICALLY, Israel's reluctance to commit troops in battle to deal with Hamas aggression signals weakness. The widespread perception within the Arab world that Israeli society is extremely sensitive to the loss of human life invites enemy violence. It was largely this perception that motivated the Palestinian terror campaign against Israel in September 2000. The "spider web" theory propagated by Hizbullah leader Hassan Nasrallah - that Israel's emphasis on the value of human life as well as its self-indulgent Western characteristics render it weak and vulnerable - are also based on this view. Nowadays, in order to terrorize Israeli citizens, Gazans count on Israel's reluctance to employ land operations and attack targets in dense population areas. ISRAELI POLICY should signal that life on the Palestinian side of the border will be invariably affected by Palestinian violence intent on deteriorating the quality of life on Israel's side of the border. Palestinian dependence on Israel for electricity and water supply should be capitalized on to impress upon the Palestinians that reciprocity is the name of the game. Israel has no obligation to the Palestinians if they are indiscriminately killing civilians and damaging valuable infrastructure. International law permits a military response, including artillery, aimed at the sources of fire, even if the fire is coming from urban areas. Israel should not hesitate to create a refugee wave by warning about impending fire on residential areas. Such tactics may result in a degree of Palestinian restraint. Moreover, the international atmosphere is very conducive to an Israeli strike on Hamas-controlled Gaza. Hamas is largely ostracized by the international community, which wants to help Mahmoud Abbas restore the authority of the PA to the Gaza Strip. Anything Israel does to weaken Hamas' grip on Gaza will be viewed with understanding. Abbas himself and his impotent coterie are quietly expecting that Israel will act to erode the control of the Hamas regime. Similarly, the so-called moderate Arab states will hardly be displeased if Hamas is weakened by Israel. The Hamas takeover of Gaza was a great shock for them as it encouraged Islamic opposition groups in their own countries. FINALLY, the US may be expecting Israel to land a blow on the radical Islamic regime. Jerusalem failed to deliver a victory against Hizbullah in the summer of 2006 and can ill afford to be again seen as ineffective. Moreover, if the West is serious about establishing a united front against the Islamic Republic of Iran, Gaza is a good place to start. Regime change should not, however, be the goal of the inevitable Israeli military onslaught in Gaza. Israel can weaken Hamas, but it cannot impose an Arab ruler over the 1.5 million Gazans. It is beyond the power of Israel, or of any Western outsider, to influence the social and political dynamics of the Gaza Strip. Reoccupation of Gaza is, therefore, also not recommended. Israel's goal should be merely defensive - to destroy Gazan capabilities to harm Israel. This means our temporary presence in all places where such capabilities are developed; their destruction and, after the evacuation of Gaza, systematic surgical strikes against reemerging terrorist cells. The model for Israeli military activity in Gaza should be the successful way Israel deals with the terrorist infrastructure in Judea and Samaria. The writer is professor of political studies at Bar-Ilan University and the director of the Begin-Sadat (BESA) Center for Strategic Studies.