For two-and-a-half years, ever since the unilateral disengagement from the Gaza Strip, the defense establishment has been warning of a "triangle of terror" connecting Gaza, Egypt and Israel. With Gaza empty of Israeli soldiers and settlers, terror groups were left with two ways to hit Israel's home front - Kassam rocket attacks or sending terrorists into Sinai, where they drive dozens of kilometers along Israel's 220-km. fenceless border with Egypt, slip into the Negev, and carry out their attack. About 130 km. to the north lies another weak point in Israeli security. The South Hebron Hills contain one of two openings - along with the Jerusalem "envelope" - remaining in the West Bank security barrier. As of Monday night, the possibility that the two Dimona terrorists came from the West Bank and used the southern opening in the fence to cross into the Negev had yet to be ruled out. The suicide attack that rocked Dimona's streets on Monday, killing one Israeli, is of strategic significance. Regardless of where the terrorists came from, the bombing demonstrates the urgency of completing both fences - along the Egyptian-Israeli border as well as in the South Hebron Hills. In both cases, the writing was already on the wall. Terrorists have infiltrated Israel after crossing into Sinai from Gaza before. The last time was in January 2007, when a suicide bomber detonated himself in an Eilat bakery, killing three Israelis. In the two years since disengagement, the IDF and Shin Bet (Israel Security Agency) have captured more than 100 terrorists who originated in the Gaza Strip and tried to cross into Israel from the Sinai Desert. The terrorists included suicide bombers, weapons experts on their way to establish terror infrastructure in the West Bank and masterminds of soldier-kidnapping plots. Security forces have also dismantled more than a dozen terror rings that had established infrastructure used for border infiltrations. This was all before the wall came tumbling down along the Gaza-Egyptian border almost two weeks ago, after which defense officials spoke of hundreds of terrorists entering Sinai, some on their way to Iran and Syria for weapons training and others planning to perpetrate attacks against Israeli border communities. On Sunday, Egyptian security forces in Sinai caught two brothers from Gaza who were wearing explosive belts, four km. west of Rafah. A day earlier, 15 armed Palestinians were apprehended in Egypt and on Monday, hours after the Dimona attack, Egyptian police announced the arrest of another Palestinian terrorist in Rafah who was in possession of an explosive device. The IDF, Shin Bet and Israel Police have done what they can. OC Southern Command Maj.-Gen. Yoav Galant deployed additional forces along the border, particularly in populated areas such as Nitzana and Eilat. The Shin Bet refocused its attention to the border area and, as evidenced by the heroic performance of police officer Ch.-Sup. Kobi Mor - who killed the second terrorist on Monday before the man could detonate his explosive belt - the police also raised its level of alert. If the bombers came from the West Bank, it would not be the first time that terrorists took advantage of the opening in the West Bank security barrier and infiltrated the southern Negev. In 2004, two terrorists from Hebron blew themselves up minutes apart on buses in Beersheba, killing 16 and wounding 100. The security barrier's 26-km. southern section has taken years to complete, at the cost of lives. At first, the government was not certain that a fence was even needed there, focusing its attention instead on the western part of the fence, which has been completed. On Monday, defense officials said it was unlikely that the barrier in the area would be completed before the end of 2009. All of these scenarios were in defense officials' minds before Israel pulled out of Gaza, but as the Winograd Report on the Second Lebanon War clearly stated last week, improvement is desperately needed in the interface between the military and political echelons. Ahead of the 2005 withdrawal, the IDF drew up a plan called "Hourglass" that called for the erection of an electronic fence along the 220-km. Egyptian border, from Rafah to Eilat. In 2005, then-prime minister Ariel Sharon visited the border together with then-chief of General Staff Lt.-Gen. Dan Halutz and called to establish a barrier at least in the 50-km. area near Eilat. In the end, however, only NIS 100 million - out of the NIS 1.5 billion needed - was transferred by the government for the entire project. Defense Minister Ehud Barak resurrected the Hourglass plan this week, but - as usual in Israeli strategic thinking - the move came in response to the breach in the Gaza-Egyptian border. It was not part of a larger strategic planning process. Unfortunately, this ad hoc approach is prevalent within both the political and defense echelons. Barak decided in mid-January to tighten the economic blockade on Gaza, but the issue was never really debated in the cabinet. As demonstrated by the minister's quick change of mind following Hamas's clear PR victory, there was never a set and clear policy in hand. Following the Dimona attack, we can expect a flurry of calls by politicians across the political spectrum to immediately erect a fence along the Israeli-Egyptian border, or, if the terrorists came from Hebron, to speed up construction of the southern part of the West Bank barrier. These fences are definitely of strategic importance, but what is no less important is for our leaders to stop formulating policy in reaction to developments on the Palestinian side.