The reaction of the Palestinian Arabs to President Trump’s new peace plan turns out to be a vow to sever relations with both Israel and America. On its face that wouldn’t be the worst outcome, either, given the prospect that our permanent State Department, egged on by our Democratic Party intelligentsia, will be tempted to try to win a compromise by tilting Mr. Trump’s plan toward the Arab camp.

Why should America be suing anyone for a Middle East peace? We have been asking that question for years. It’s not that the Sun opposes peace in the Middle East. We don’t. Nor do we lack for regard for President Trump, whom we endorsed (partly on the basis of his seichel in respect of Israel). We also have great regard for the President’s son-in-law, Jared Kushner, scion of a revered Zionist family.

We can see, moreover, that the vision — known as “Peace to Prosperity” — that Mr. Trump unveiled on Tuesday has some favorable features lacking in previous plans. Even the Zionist Organization of America issued a press release praising certain elements of the plan. These start with its acknowledgement that Israel has asserted “valid legal and historical claims” to the territory it’s being asked to transfer.

The vision also frees Israel from the canard that it is somehow bound by the United Nations to retreat to the 1967 lines. The plan would uproot no settlements. Israel would retain sovereignty over the Jordan Valley and also its territorial waters. It protects Israel’s Jewish sites. It would keep the American embassy in Jerusalem. Importantly, it vouchsafes the right of Jews, among others, to pray on the Temple Mount.

The ZOA praises 30 points in the plan. Prime Minister Netanyahu and his leading opponent, General Gantz, both have made supportive statements. The plan is also being given a guardedly positive reception by Egypt, Saudi Arabia, Kuwait, Qatar and the United Arab Emirates. The Times of Israel characterizes them as indicating that the plan could be the basis for negotiations that “the Palestinians should seize.”

Fair enough, but it would be a mistake to attempt to cajole the Palestinian Arabs in any way. Instead, this is a moment for our side to study “The Iron Wall.” That is the 1923 essay by the Zionist prophet Vladimir Jabotinsky, warning against supposing that there could be a voluntary agreement between Zionism and the Palestinian Arabs. He did not think they could be bought and opposed attempts to do so.

Hence the logic of an “iron wall,” that is, an unassailable military defense of the Jews in the land of Israel — and, eventually, a Jewish state — until the Arabs give up hope of expelling them. That is, until they decide, in a calculation of their own interests, to come to terms. If one believes in that wisdom, then all the pleading with the Palestinians to come to the peace table has been counterproductive.

Successive American governments have been wheedling for years. The result, we’ve long since concluded, has been to embolden the Arabs to hold out, while an over-eager peace camp in America has plumped for better terms for the Arabs. The reason Mr. Netanyahu is calling Mr. Trump the greatest friend Israel has had in the White House is that he seems to grasp this problem.

All the greater is the danger that the plan Mr. Trump has just unveiled will incite the Democrats and others on the left to — yet again — launch a campaign to pressure Israel into being more accommodating than it wants, or needs, to be. The New York Times has already come in with a condescending editorial calling the Trump plan a “sop” to the right wing bases of Messrs. Trump and Netanyahu.

In an emergency meeting today at Cairo, Mahmoud Abbas won the unanimous support of the Arab League. The Palestinian Arab leader is due in New York next week to present to the United Nations Security Council a resolution against the plan. It’s hard to imagine that it won’t be vetoed by the United States. The 84-year-old unelected “president” of the Palestinian Authority is the only one under any time pressure for peace, and he has no political heir.