This week’s revelation of a massive Hamas attack tunnel stretching from southern Gaza to Israel’s Eshkol region is a reminder that the terrorism industry in Gaza is pushing ahead at full throttle, in anticipation of the day that the cease-fire between Hamas and Israel will come to an end.The proportions and engineering of the latest tunnel exposed by the IDF are staggering: It is 1.7 kilometers long and 1.80 meters tall, complete with an electricity supply and telephone communications.Some 24,000 cement slabs were used in its construction, to reinforce the subterranean structure; this was cement Israel sent to Gaza in order to assist the civilian construction sector. In light of the fact that it was the third tunnel to be uncovered this year, the IDF is working on the assumption that there are more undiscovered tunnels out there, and that Hamas is going to continue to try and dig its way under army forces patrolling the border, toward frontier towns and villages.The tunnels present a double threat to Israeli security. The first lies in Hamas’s ambitions to capture and kidnap IDF soldiers to trade for the release of Palestinian security prisoners in Israeli jails, in a bid to replicate their successful Gilad Schalit exchange.The second threat involves a scenario of Hamas gunmen walking through the tunnels under the border and sneaking into a civilian community to carry out a terrorist atrocity.The tunnel is just one aspect of a wider Hamas effort to rebuild its guerrilla military and terrorist capabilities following its bruising clash with Israel in November 2012. These efforts include restocking its short- and medium-range rockets. Hamas has at least 5,000 short-range rockets that put southern cities like Ashkelon and Ashdod in range, and is attempting to create a new arsenal of rockets that can hit Tel Aviv and Jerusalem.It is training and building up its fighting forces, composed of 16,000 armed men. On the Israeli side of the border, the IDF isn’t resting on its laurels. The Southern Command is enjoying an unprecedented level of intelligence on Hamas’s activities (as well as information on Islamic Jihad and smaller al-Qaida-affiliated organizations in Gaza). This intelligence can, in any future round of fighting, guide the IDF’s devastating guided firepower. From the air, the IAF can hit well over 1,000 targets daily, and a ground offensive would threaten Hamas’s future existence as a ruling regime.On a day-to-day basis, the IDF deploys heavy border patrols and monitors Gaza, with the help of advanced border and aerial surveillance systems.Aware of Israel’s might, Hamas is playing a delicate balancing act, seeking to prepare surprises for Israel without directly attacking it from Gaza.The fact that Hamas is completely isolated in the region only contributes further to Israeli deterrence against it.With the fall of the Muslim Brotherhood from power in Cairo, Hamas’s ambition to fall under the wings of its fellow Egyptian Islamists and set up a regional alliance of Islamist entities to threaten Israel, has been replaced with an anxious search for new allies, and an attempt to fall back into the Iranian orbit.The Egyptian military administration, under the leadership of Gen. Abdel Fatah al-Sisi, has identified Hamas as a hostile branch of its domestic foe the Muslim Brotherhood, and sees Gaza as a dangerous strip of land that can be used by terrorists to smuggle weapons and fighters into Sinai to attack the Egyptian army. As a result, Egypt’s military has sealed off many smuggling tunnels linking Sinai to Gaza, contributing to Hamas’s growing isolation.Deterrence and isolation should keep the ceasefire with Hamas going for a while longer, but Hamas’s increasingly desperate situation might push it towards strategic errors and cause it to attack Israel.Hence, the IDF felt the need to reemphasize its intentions to hit Hamas very hard should it decide to use one of the tunnels soon.“This is the third tunnel we’ve found this year,” Southern Command chief Maj.-Gen. Sami Turgeman told reporters this week, speaking near the tunnel’s entrance.“It constitutes a gross violation of Israeli territory.If Hamas carries out a terrorist attack, it will pay a heavy prize, and Gaza will look different afterwards,” he warned.By telling Hamas that Israel is serious about using overwhelming force in the event of a breakdown in the cease-fire, the IDF increases the chances of maintaining the current period of calm.