Ever since Israel reacted to the fall of Bashar al-Assad by sending the IDF to keep its border with Syria demilitarized, it has faced criticism for its aggressive posture.

Those complaints have aged like milk in August. And in one recent case, Israel’s intervention came not a moment too soon.

When Assad was first overthrown by the rebel armies led by Ahmed al-Shara, a former al-Qaeda figure, Israel moved immediately to create a buffer zone just beyond the Israeli-Syrian border, including the area around Mount Hermon. Then the IDF pushed to demilitarize the area between Damascus and that buffer zone, all the while eliminating chemical-weapons depots and arms stockpiles that could be used by the remnants of the Iran-directed Assadists left in the country. More generally, securing that buffer zone was an attempt to prevent the creation of a lawless region that could become a playground for Islamist militias beyond the control of the central government, similar to the one that has long predominated in South Lebanon.

Beyond the obvious rationality of this goal, there was also the question of timing: If Israel didn’t act fast enough it would lose its window to act at all. So while much of the world wanted Shara to have a chance to set up a new government without outside interference, it was simply unreasonable to ask Israel to join the honeymoon. After all, Israel has been fighting a multi-front war precisely because power vacuums were allowed to develop on its other borders.

Israel’s desire for Syrian stability has long been a point of policy divergence between Jerusalem and much of the West, going back to the Arab Spring. Fearing chaos in its backyard, Israel looked on with some trepidation as the civil war dragged on for a decade.

But Israel and the U.S. do have the same long-running allies inside Syria in the Druze and Kurdish communities, and Israeli and American interests are largely aligned on that count. The Kurds have taken the lead in America’s anti-ISIS coalition in the region; they currently guard about 20 prisons full of ISIS militants as well as camps holding relatives of those fighters. Shara’s key patron, Turkey, is a sworn enemy of the Kurds and thus Kurdish security cannot be taken for granted.

When it comes to the Druze, the situation is a bit more personal for Israel. There are about 150,000 Druze living in Israel; 25,000 or so on the Golan Heights alone. The Druze serve in the IDF as well.

According to some reports, Israel offered work permits to Druze living in the Syrian buffer zone. Then last week Israel made its position more explicit: The Druze minority in Syria were to be left alone, a suggestion that they were under an Israeli security umbrella. Another possibility was that, as Turkish saber-rattling against the Kurds increased, the U.S. and Israel were securing opposite ends of a corridor that would run through Kurdish territory and neighboring Druze territory into the Israeli buffer zone.

A couple of weeks ago, the Washington Post complained about Israel’s intervention, saying “the source of the danger to Israel was unclear.” But this week everything became clear—and the danger wasn’t necessarily to Israel directly but did justify Israel’s involvement.

Government security personnel have been seeking to secure the loyalty of various Syrian minority armed groups in recent days. When Shara’s men held talks with Druze leaders, it was after Israel’s warning. Damascus ended up granting the Druze militias autonomy and permission to keep their weapons. It was a major win for the Druze. “Israel’s intervention may well have convinced Damascus of the necessity for such a compromise,” commented Joshua Landis, an occasional informal adviser to past Democratic administrations on Syria.

Shara’s attempts to get other factions under control, in contrast, have been disastrous. Security personnel went into Latakia, Syria’s key port and a stronghold of Assad loyalists, where the latter were waiting for them with guns drawn. Sixteen government security men were killed. Shara then stepped up attempts to pacify Latakia and Tartus, another port city, where his forces clashed further with Assad loyalists. By Friday afternoon, about 150 people had been killed in the two-day skirmish and the new Syrian government was in danger of losing control over the Mediterranean coast.

Israel’s worries, it turned out, were far from unfounded; they were prescient. Nature abhors a vacuum, and the Israeli security establishment’s pessimistic instincts were on target. Post-Oct. 7, Jerusalem is serious about keeping complacency off the menu.