The more President Obama maneuvers in pursuit of a deal with Iran, the more it looks like what he’s really intent on is a separate peace. No wonder Israel and Congress are up in arms.

A “separate peace” is when a country breaks from an ally and cuts a deal with a former enemy. It’s what Russia did in World War I, when, after the Bolsheviks seized power, they wrote up, at Brest-Litovsk, a peace with Germany.

It’s also what Britain and France did before World War II when they signed their appeasement deal with Hitler at Munich. They could have stood with their ally. But the doughty Czechs were not at the table when Britain and France met Hitler and handed much of Czechoslavia to the tyrant.

That central feature of the appeasement story is told in, among other places, William Shirer’s “Rise and Fall of the Third Reich.” Shirer writes of how Britain’s parliament erupted in joy when Prime Minister Neville Chamberlain announced he would go to Munich. Yet Czechoslovakia’s minister in London, Jan Masaryk, sitting in the visitors’ gallery, was horrified.

He raced to meet with Chamberlain and his foreign secretary, Lord Halifax, and demanded to know whether the Czechs would be included in the talks. When they said that Hitler wouldn’t allow it, Shirer writes, Masaryk was stunned (his father had founded the country that was about to be lost). He “gazed at the two God-fearing Englishmen and struggled to keep control of himself.”

“If you have sacrificed my nation to preserve the peace of the world, I will be the first to applaud you,” Shirer quotes Masaryk as responding. “But if not, gentlemen, God help your souls.”

When Prime Minister Netanyahu gives his speech to Congress, it wouldn’t be inapt for him to talk about Munich. After all, why doesn’t Israel have a seat at the negotiations with Iran? The talks are called the P5+1 — for the five permanent members of the UN Security Council plus Germany.

It’s Israel that Iran vows to wipe off the map. Why not the P5+2?

One way to look at Mr. Netanyahu’s speech to Congress is that it gives him a voice at the talks where the Iranian mullahs won’t allow him. (They won’t even let their athletes compete against Israelis.)

At the moment, it looks like Congress is holding its ground on Mr. Netanyahu. In the latest numbers circulated by the Israel Project, only 12 members of the House and two senators have indicated they’ll boycott Mr. Netanyahu.

The Senate’s announced boycotters are both from Vermont, Bernard Sanders, a socialist, and Patrick Leahy, a Democrat who blames the GOP leadership for orchestrating what he calls a “tawdry and high-handed stunt.”

They may be joined by others, perhaps even a New York senator: Charles Schumer has said he’ll attend, but Kirstin Gillibrand hasn’t.

Congress can be fickle — just ask the people of South Vietnam, whom the Congress two generations ago notoriously betrayed (by refusing to let President Ford send the supplies the South needed to fend off the communist army).

At the moment, though, it looks like the overwhelming majority of the House and Senate will be present to hear Mr. Netanyahu. They’re considering the Nuclear Weapon Free Iran Act, which would restore — and even tighten — sanctions if Iran defaults on a deal.

The measure, launched by Senators Robert Menendez, Democrat of New Jersey, and Mark Kirk, Republican of Illinois, has bipartisan support. It would be an important check and balance on the president.

Yet beware. Menendez-Kirk includes waiver authority to let the president suspend any restored or new sanctions for 30 days and keep suspending them. A similar waiver provision has allowed the State Department to dodge moving our Israel embassy to Jerusalem for decades.

So this is a timely juncture for Mr. Netanyahu to address Congress. Precisely because he is the son of a historian — and a superb one — he will know all about the precedents of a separate peace.

The New York Times denounced the perfidious peace at Brest-Litovsk, warning it “will be neither honorable nor lasting.” The New York Sun called it “Bolshevik treason.”

And the New York Herald thundered: “The Bolsheviki think they are Russia. They are not.”

That’s a point to remember as Obama races for a separate peace with a regime that has no democratic mandate and rails at one of the few leaders in the Middle East who does.

This column originally appeared in the New York Post.