The Israeli prime minister Menachem Begin famously told American diplomats, who were offering international security reassurances to back up a putative peace deal with the Palestinians, that “there is no guarantee that can guarantee a guarantee.” This has not prevented similar arrangements from being proposed ever since. But, as David Makovsky notes, Israel had learned Begin’s dictum the hard way in 1967:

After the Suez Crisis of 1956, Prime Minister David Ben-Gurion conceded in principle to withdraw from the Sinai Peninsula, but requested several assurances before Israel could move ahead: among the assurances he sought were that the Straits of Tiran wouldn’t be blockaded again. . . . He also sought assurance that the UN Emergency Force in the Sinai couldn’t be withdrawn just due to the sole demand of the Egyptians.

President Dwight Eisenhower felt Israel was obligated to withdraw [its forces from the Sinai] and could not put forward conditions for a pullout. At the same, he acknowledged, it had legitimate concerns. To square this circle in March 1957, he offered Israel a text known as an aide-mémoire through the State Department, . . . explicitly stating that blocking the Straits of Tiran was unacceptable. It implied but did not state that the U.S. would be willing to use military means to back up its words. . . .

On May 22, 1967, Egypt’s President Gamal Abdel Nasser closed the straits, a critical blow to Israel which relied on oil imports [shipped via the straits] from Iran. . . . In the wake of Nasser’s move on the straits, Prime Minister Levi Eshkol dispatched his foreign minister, Abba Eban, on a whirlwind trip to Paris, London, and Washington, to see if the international community would re-open the straits and avert war. . . . Charles de Gaulle, then [the president of France] declared, “that was 1957.” . . . President Lyndon Johnson was preoccupied with Vietnam, and his aides had to scurry to Eisenhower’s retirement residence in Gettysburg, Pennsylvania, to find out what had been promised. . . .

[T]he notion that international guarantees are not ironclad should not be confused with the thinking that Israel should rely only on force. The peace treaty between Egypt and Israel of 1979 and the peace treaty between Jordan and Israel of 1994 have withstood enormous regional and bilateral shocks in the last few decades. . . . [But if] the chips are down, Israel needs to be able to defend itself by itself.

Concluded in 1979, the Israeli-Egyptian peace treaty ended nearly 30 years of intermittent warfare, and proved one of the most enduring and beneficial products of Middle East diplomacy. But Egypt may not have been upholding its end of the bargain, write Jonathan Schanzer and Mariam Wahba:

Article III, subsection two of the peace agreement’s preamble explicitly requires both parties “to ensure that that acts or threats of belligerency, hostility, or violence do not originate from and are not committed from within its territory.” This clause also mandates both parties to hold accountable any perpetrators of such acts.

Recent Israeli operations along the Philadelphi Corridor, the narrow strip of land bordering Egypt and Gaza, have uncovered multiple tunnels and access points used by Hamas—some in plain sight of Egyptian guard towers. While it could be argued that Egypt has lacked the capacity to tackle this problem, it is equally plausible that it lacks the will. Either way, it’s a serious problem.

Was Egypt motivated by money, amidst a steep and protracted economic decline in recent years? Did Cairo get paid off by Hamas, or its wealthy patron, Qatar? Did the Iranians play a role? Was Egypt threatened with violence and unrest by the Sinai’s Bedouin Union of Tribes, who are the primary profiteers of smuggling, if it did not allow the tunnels to operate? Or did the Sisi regime take part in this operation because of an ideological hatred of Israel?