Rep. Keith Ellison’s selection as deputy chairman of the Democratic National Committee is the latest ratification of our party’s turn away from Israel. Mr. Ellison, who complained in 2010 that “United States foreign policy in the Middle East is governed by what is good or bad through a country of seven million people,” narrowly lost a bid for DNC chairman, then was chosen by acclamation as deputy.

The Democrats used to be the pro-Israel party. President Truman recognized the Jewish state within minutes of its independence...