Over the past week, differences between Israel and the United States have boiled over into a scalding diplomatic confrontation between these closest of allies. The dispute reflects not any change in American policy, but a dangerous evolution in Israeli policy, under the government of Prime Minister Benjamin Netanyahu, away from an acceptance of a negotiated two-state resolution to Israel’s conflict with the Palestinians. The dispute also arises from Mr. Netanyahu’s lamentable practice of making his government a more nakedly partisan player in American politics than any foreign government in memory, save Russia.

It is hard to see how either move by this Israeli government serves Israel’s long-term interest.

The spark for this confrontation was a United Nations Security Council resolution, adopted on Friday, that condemned Israeli settlement-building in the West Bank and East Jerusalem. The Obama administration chose to abstain from the vote rather than exercise its veto to block it. The United Nations is shamefully biased against Israel, and President Obama has used the American veto and its diplomatic muscle more assiduously than any previous American president to shield Israel from unwarranted criticism. But nowhere is it written that an American president is obliged to shelter Israel from international criticism that is consistent with decades-old American policy and with American interests.

The American abstention has triggered more than the usual amount of outrage, name-calling and threats from Mr. Netanyahu and his allies. Personalizing the dispute to an astonishing degree, they have accused Mr. Obama of betraying Israel.

They’re wrong. Many of Mr. Netanyahu’s accusations and those of his supporters misrepresent the history of Israeli-American relations, malign Mr. Obama and his secretary of state, John Kerry, and confuse what should be a serious debate over the future of a negotiated peace between Israelis and Palestinians, which seems further away every day. With less than three weeks before Mr. Obama leaves office, Mr. Kerry on Wednesday finally gave the speech he wanted to give two years ago — a passionate, blunt and detailed warning about why the two-state solution is in jeopardy and how it might yet be salvaged before incalculable damage is done to Israel and the region.