The fourth tunnel exposed on Israel’s border with Lebanon will not be the last. The digging of these tunnels has been going on for years. The timing of the operation has nothing to do with when the tunnels were discovered and everything to do with when the officials wanted to reveal their existence to the public.

We can only hope the exposure will silence the curious criticism coming from some in the media, among others, over the Israel Defense Forces’ use of the term “operation” to describe these efforts, whose importance was apparent with the exposure of the first terror tunnel. This is an operation that has been going on in the area for some time and involves quite a few forces, including explosions and engineering work covering a wide area.

The digging of a tunnel under the border is a terrorist activity by any definition; it is tantamount to the firing of rockets over the border fence or an attempt to infiltrate the border. Terrorism must be fought on a number of fronts: diplomatic, military, economic, legal and the public conscience.

From a diplomatic perspective, Israeli Prime Minister and Defense Minister Benjamin Netanyahu was right to hold not only Hezbollah, but also the Lebanese government responsible. Lebanon has been playing the part of the helpless country unable to influence Hezbollah for far too long. The time has come for Beirut to understand that it could pay a heavy price for this hypocrisy.

Netanyahu discussed the issue with Russian President Vladimir Putin and others, and dispatched intelligence officials to the United States for a briefing ahead of a meeting of the U.N. Security Council. Tours of the area, press conferences, ambassador briefings and the like are part of the diplomatic efforts, as well as efforts to influence public conscience. While this does not ensure that a just decision will be reached by the U.N. Security Council, it is nevertheless important to arrive at these meetings armed and ready.

As far as Israel’s military efforts on the issue are concerned, exposing the threat of an attack on Israeli communities, border infiltration, the kidnapping of citizens and soldiers, and thwarting that threat are important, but not enough. We must not deal solely with the barrel of the gun protruding into our territory, but also with the gun itself, the ammunition and the person planning to pull the trigger.

The IDF has begun to seal off the entrances to the tunnels on our side of the border and detonate them along the way—a move one IDF spokesperson said would ensure they have been taken out of operation on the Lebanese side as well. Now the time has come to detonate the entire length of the tunnels, and more importantly, deal with their points of origin in Lebanon. A massive explosion would not only neutralize Hezbollah’s ability to go back and dig a new tunnel, but would financially punish those who put their greenhouse, field or factory at the terrorist group’s disposal.

There is nothing sacred about keeping the operation on our side of the border, especially when there are no fences underground and the risks have been calculated in advance. Furthermore, Israel is known to have at its disposal not only drones but also self-driving vehicles. That is how you achieve deterrence.

There are those who warn against any move that could lead to an escalation in tensions and possibly influence other fronts. But it is precisely because we have other fronts—Iran, the Gaza Strip, Judea and Samaria, the north and the homefront—that we must be strong and determined in our response. Should Israel suffice with defensive action, the insolence of Iran and its emissaries will continue to grow, and there will be increasing support for the use of this type of aggressive infrastructure from the regimes in Lebanon, Syria and Iran.

Our enemies must know that while America may pull out of Syria and reduce its presence in the region, we are here to stay.

Maj. Gen. (ret.) Uzi Dayan was Israel’s former deputy chief of staff.