“Why would you ask that question?” I asked, even though I realized I might not be helping the person using me as a reference. He answered, “Because he is Jewish.” So I went on: If he was Irish and had to work on problems related to Ireland or if he was Italian and had to work on Italy, would you ask that question? Initially, the investigator did not seem to know how to respond, but then I saw a look of recognition. He suddenly realized that I was Jewish. And, at that point, he changed the subject.

This investigator was not a rookie. And his experience with senior State Department officials led him to believe it was natural to ask this question. Like most mythologies which take on a life of their own, the idea that Jewish-Americans might have dual loyalties was not challenged or questioned, it was assumed. That made it all the more insidious.

Just like Ms. Wilson tweeting that Jews are pushing for a new war. It is the definition of prejudice. How can it not be when you label a whole group and ascribe to all those who are a part of it a particular negative trait or threatening behavior? It is the same today with those who single out all Muslims as dangerous extremists. It is just as unacceptable.

Today, surging nationalism and xenophobia promise to create even more prejudice. These attitudes foster an “us versus them” mentality. The “other” is a threat. And once you have singled out groups, the leap is small to imposing limits on them, quarantining them and rationalizing violence against them.

Rather than be worried about being mistrusted and accused of dual loyalties, Jewish Americans should feel proud. In uncertain times, identity can provide a source of security and comfort. And having a strong identity, being comfortable with who you are and whom you are connected to, need not come at the expense of others. As my rabbi, Jonathan Maltzman, pointed out in his Rosh Hashana sermon, the particular and the universal have always been embedded in Jewish identity.

Indeed, to live a Jewish life one must be committed to the Jewish community, but also to others. Jews have an obligation to promote justice, mercy, compassion, tolerance and peace.

In the United States, diversity of peoples and opinions is our strength as a democracy. Listening to one another, as opposed to labeling one another, can restore civil debate. It is certainly the only way to produce better policies. And it might even introduce greater care and civility to Twitter.