Forty years ago this month, Israel launched what is now known as the First Lebanon War, with the aim of driving the Palestine Liberation Organization (PLO) from Lebanese soil. Lazar Berman explains:

Kiryat Shmona, a small Israeli city a short distance from the Lebanon border, had indeed been burning over the previous year. The Palestine Liberation Organization’s Katyusha fire from inside Lebanon in July 1981 had caused residents to flee, and rockets continued to rain down over the ensuing months. The final straw came on June 3, 1982, when members of the Palestinian Abu Nidal Organization tried to assassinate Israel’s ambassador in London, Shlomo Argov, leaving him in a coma until his death in 2003.

The campaign was seen as an entirely justified operation against the Palestinian terrorists who were firing rockets on border towns, slaughtering passengers on buses, and shooting Israeli diplomats in Europe.

Although the most intense fighting was over in a few months, and the main part of the war lasted only until 1985, the IDF would remain in Lebanon until 2000, as it found itself dragged into conflict with the Syrian army, various Lebanese factions, and eventually Hizballah. The war succeeded in ousting the PLO from Lebanon, yet it is remembered by Israelis much as the Vietnam war is remembered by Americans. Berman analyzes its enduring legacy:

Israel has . . . become extremely skittish about capturing ground, once seen as the key to victory. Now, the fear of getting stuck occupying hostile territory leads military planners to design campaigns around air and artillery fire, resorting to ground maneuvers only as a last resort, and only when they know how and when forces are going to leave. The tentative and ineffectual ground maneuver in Lebanon in 2006 and the limited incursions in the rounds of fighting in Gaza are symptoms of this Lebanon syndrome.

The failed effort in 1982 to install a friendly government in Beirut also restricts Israel’s foreign policy four decades later. Before the war, Israel built ties with a range of proxies across the Middle East and beyond, including in Iraqi Kurdistan, Yemen, and of course, Lebanon. But since sinking into the Lebanese mud, Israel has been careful to keep its boots clean. Iran, meanwhile, has turned its proxy forces into valuable assets in the region.

Last month saw yet another round of fighting between the Jewish state and Gaza-based terrorist groups. This time, it was Palestinian Islamic Jihad (PIJ) that began the conflict; in other cases, it was Hamas, which rules the territory. Such outbreaks have been numerous in the years since 2009, and although the details have varied somewhat, Israel has not yet found a way to stop them, or to save the residents of the southwestern part of the country from the constant threat of rocket fire. Yossi Kuperwasser argues that a combination of military, economic, and diplomatic pressure might present an alternative solution:

In Gaza, Jerusalem plays a key role in developing the rules that determine what the parties can and cannot do. Such rules are designed to give the Israelis the ability to deter attacks, defend territory, maintain intelligence dominance, and win decisively. These rules assure Hamas that its rule over Gaza will not be challenged and that, in between the rounds of escalation, it will be allowed to continue its military buildup, as the Israelis seldom strike first, and the government’s responses to Hamas’s limited attacks are always measured and proportionate.

The flaws in such an approach are clear: it grants Hamas the ability to develop its offensive capabilities, increase its political power, and condemn Israelis—especially those living within range of the Gaza Strip—to persistent threats from Hamas terrorists.

A far more effective [goal] would be to rid Israel of Hamas’s threat by disarming it, prohibiting its rearmament, and demonstrating conclusively that threatening Israel is indisputably against its interests. Achieving this goal will not be easy, but with proper preparation, it may be feasible at the appropriate time.

Revisiting the rule according to which Jerusalem remains tacitly committed to not ending Hamas rule in Gaza is key for changing the dynamics of this conflict. So long as Hamas knows that the Israelis will not attempt to uproot it from Gaza, it can continue arming itself and conducting periodic attacks knowing the price it will pay may be heavy—especially if Jerusalem changes the other rules mentioned—but not existential.