The world is about to mark the 50th anniversary of the June 1967 war between Israel and Egypt, Jordan, and Syria—a conflict that continues to stand out in a region with a modern history largely defined by violence. The war lasted less than a week, but its legacy remains pronounced a half-century later.

The war itself was triggered by an Israeli preemptive strike on the Egyptian air force, in response to Egypt’s decision to expel a United Nations peacekeeping force from Gaza and the Sinai Peninsula and to close the Straits of Tiran to Israeli shipping. Israel struck first, but most observers regarded what it did as a legitimate act of self-defense against an imminent threat.

Israel did not intend to fight on more than one front, but the war quickly expanded when both Jordan and Syria entered the conflict on Egypt’s side. It was a costly decision for the Arab countries. After just six days of fighting, Israel controlled the Sinai Peninsula and the Gaza strip, the Golan Heights, the West Bank, and all of Jerusalem. The new Israel was more than three times larger than the old one. It was oddly reminiscent of Genesis: six days of intense effort followed by a day of rest, in this case the signing of a cease-fire.

The one-sided battle and its outcome put an end to the notion (for some, a dream) that Israel could be eliminated. The 1967 victory made Israel permanent in ways that the wars of 1948 and 1956 did not. The new state finally acquired a degree of strategic depth. Most Arab leaders came to shift their strategic goal from Israel’s disappearance to its return to the pre-1967 war borders.

The Six-Day War did not, however, lead to peace, even a partial one. That would have to wait until the October 1973 war, which set the stage for what became the Camp David Accords and the Israel-Egypt peace treaty. The Arab side emerged from this subsequent conflict with its honor restored; Israelis for their part emerged chastened. There is a valuable lesson here: decisive military outcomes do not necessarily lead to decisive political results, much less peace.

The 1967 war did, however, lead to diplomacy, in this case UN Security Council Resolution 242. Approved in November 1967, the resolution called for Israel to withdraw from territories occupied in the recent conflict—but also upheld Israel’s right to live within secure and recognized boundaries. The resolution was a classic case of creative ambiguity. Different people read it to mean different things. That can make a resolution easier to adopt, but more difficult to act on.

It thus comes as little surprise that there is still no peace between Israelis and Palestinians, despite countless diplomatic undertakings by the United States, the European Union and its members, the UN, and the parties themselves. To be fair, Resolution 242 cannot be blamed for this state of affairs. Peace comes only when a conflict becomes ripe for resolution, which happens when the leaders of the principal protagonists are both willing and able to embrace compromise. Absent that, no amount of well-intentioned diplomatic effort by outsiders can compensate.

But the 1967 war has had an enormous impact all the same. Palestinians acquired an identity and international prominence that had largely eluded them when most were living under Egyptian or Jordanian rule. What Palestinians could not generate was a consensus among themselves regarding whether to accept Israel and, if so, what to give up in order to have a state of their own.

Israelis could agree on some things. A majority supported returning the Sinai to Egypt. Various governments were prepared to return the Golan Heights to Syria under terms that were never met. Israel unilaterally withdrew from Gaza and signed a peace treaty with Jordan. There was also broad agreement that Jerusalem should remain unified and in Israeli hands.

But agreement stopped when it came to the West Bank. For some Israelis, this territory was a means to an end, to be exchanged for a secure peace with a responsible Palestinian state. For others, it was an end in itself, to be settled and retained.

This is not to suggest a total absence of diplomatic progress since 1967. Many Israelis and Palestinians have come to recognize the reality of one another’s existence and the need for some sort of partition of the land into two states. But for now the two sides are not prepared to resolve what separates them. Both sides have paid and are paying a price for this standoff.

Beyond the physical and economic toll, Palestinians continue to lack a state of their own and control over their own lives. Israel’s objective of being a permanent Jewish, democratic, secure, and prosperous country is threatened by open-ended occupation and evolving demographic realities.

Meanwhile, the region and the world have mostly moved on, concerned more about Russia or China or North Korea. And even if there were peace between Israelis and Palestinians, it would not bring peace to Syria, Iraq, Yemen, or Libya. Fifty years after six days of war, the absence of peace between Israelis and Palestinians is part of an imperfect status quo that many have come to accept and expect.