Mearsheimer and Walt’s focus on the Israel lobby’s influence on America’s Middle East policy is grossly overblown. They portray U.S. politicians as being either too incompetent to understand America’s national interest, or so undutiful that they would sell it to any pressure group for the sake of political survival. Sentiment and idealism certainly underlie America’s commitment to Israel. But so do the shared interests and considerations of realpolitik.

President Richard Nixon, no friend of the Jews, sided with Israel during the 1973 Yom Kippur War not to protect Israel from Soviet invasion, but to serve America’s national interest. Israel was just a pawn in Nixon’s great game of the Cold War, and it was thanks to U.S. arms shipments to Israel that America was able to disrupt the Soviet-Egyptian alliance, eventually dismantling Soviet hegemony in the region. Two decades later, according to President George H.W. Bush, “thousands of lobbyists”—presumably many of whom were Jewish—fought his policy, but that did not prevent him from dragging then Israeli Prime Minister Yitzhak Shamir to a peace conference in Madrid against his will. Nor did “the lobby” prevent Bush’s predecessor, Ronald Reagan, from distancing himself from Israel by officially recognizing the Palestine Liberation Organization. And it did not stop President Bill Clinton from offering unconditional sovereignty to the Palestinians on the Temple Mount, the holiest of Jewish sites.

The United States, Mearsheimer and Walt would have us believe, has failed to force Israel to offer the Palestinians a viable state, and it has consistently backed the Israeli approach to peace negotiations. These uninformed assertions misunderstand America’s role. The Palestinians have never really expected...