No country should have to endure the rocket attacks that Israel has endured from militants in Gaza, most recently over the past four days. The question is how to stop them permanently.

On Wednesday, Israel launched one of the most ferocious assaults on Gaza since its invasion four years ago. At least 20 targets were struck and a Hamas military commander, Ahmed al-Jabari, was killed. Israeli leaders also threatened another ground war.

Hamas has controlled Gaza since Israel withdrew in 2007. The group has mostly adhered to an informal cease-fire with Israel after the war there in the winter of 2008-09. But, in recent months, Hamas has claimed responsibility for participating in rocket firings, and last week it took credit for detonating a tunnel packed with explosives along the Israel-Gaza border while Israeli soldiers were working nearby.

Israel has a right to defend itself, but it’s hard to see how Wednesday’s operation could be the most effective way of advancing its long-term interests. It has provoked new waves of condemnation against Israel in Arab countries, including Egypt, whose cooperation is needed to enforce the 1979 peace treaty and support stability in Sinai.

The action also threatens to divert attention from what Prime Minister Benjamin Netanyahu has repeatedly described as Israel’s biggest security threat: Iran’s nuclear program.

Engaging in a full-scale ground war is especially risky. Israel’s last major military campaign in Gaza was a three-week blitz in 2008-09 that killed as many as 1,400 Palestinians, and it was widely condemned internationally. It did not solve the problem. Hamas remains in control in Gaza and has amassed even more missiles.

Some Israeli commentators have suggested that Mr. Netanyahu’s decision to order the operation is connected to elections in January. But there are other options. Israel could have asked Egypt, whose new Islamist-led government has close ties to Hamas, to mediate a more permanent cease-fire. On Monday, Hamas hinted that it was open to that. Or Israel could have responded as it usually has in recent years, avoiding high-profile assassinations while attacking rocket-launching squads, empty training sites and weapons manufacturing plants.

Hamas is a dangerous adversary that may never accept Israel’s right to exist. But it would be easier to win support for retaliatory action if Israel was engaged in serious negotiations with Hamas’s rival, the Palestinian Authority, and working toward a durable peace agreement.