In the last few weeks, an uncharacteristic rift has opened between the United States and Israel, provoked by the announcement that Prime Minister Benjamin Netanyahu will address Congress in March at the invitation of House Republicans. His speech, contrary to diplomatic custom, was planned without notifying the White House and the president, who happens to be a Democrat.

Simultaneously, a website in Israel has been advertising package deals for couples who want to get married in Cyprus. For roughly $500 to $750, the betrothed get round-trip airfare, two nights in a hotel and the ceremony. Champagne and a limousine are extra. The ad appears in both Hebrew and Russian-language versions, the latter aimed at Israel’s numerous immigrants from the former Soviet Union.

Though seemingly unrelated, the Cyprus weddings and Mr. Netanyahu’s impending address are two facets of the same broader issue: the potential alienation from Israel of a large number of American Jews.

Commentators like Jeffrey Goldberg in The Atlantic and Thomas L. Friedman in The New York Times have pointed to the risk that Mr. Netanyahu’s apparent alignment with Republicans will erode the support of that majority of American Jews who reliably vote Democratic because they lean liberal on most social and economic issues.