Accustomed as he is to public speaking here and around the country, David Harris, the executive director of the American Jewish Committee, can read an audience as well as anyone. Lately, he says, he is "hearing a growing number of questions and concerns about the U.S.-Israel relationship, and a sense that the Obama administration’s response to the Iran crisis was slower than it should have been." Harris is not alone. Abraham Foxman, director of the Anti-Defamation League, says the normal anxiety level among American Jews when a new administration takes shape has been heightened to new levels because President Obama...