Valerie Plame had to know what she was tweeting. Plame retweeted a virulently anti-Semitic article by a well-known bigot, which she characterized as "thoughtful." Now she's trying to make excuses, but they don't wash.

The article by Phillip Giraldi itself contains the usual anti-Semitic tropes: Jews are guilty of dual loyalty; they control politicians, the media and entertainment; they want the U.S. to fight wars for the country to which they have real allegiance – Israel; they are dangerous to America. Giraldi has been pushing this garbage for years, and Plame is one of his fans.

But this particular article goes much further in its neo-Nazi imagery. It advocates that "The media should be required to label [Jews such as Bill Kristol] at the bottom of the television screen whenever they pop up … That would be kind-of-like a warning label on a bottle of rat poison – translating roughly as ingest even the tiniest little dosage of the nonsense spewed by Bill Kristol at your own peril."

In other words, Jewish supporters of Israel, such as Kristol and I, should have to wear the modern-day equivalent of a yellow star before we are allowed to appear on TV and "poison" real Americans. Nice stuff that Plame was retweeting and characterizing as thoughtful.

This was not the first time Plame retweeted Giraldi's garbage. In 2014, she retweeted one of his screeds with the following notation: "Well put." And after tweeting the current anti-Semitic article she described it as: "Yes, very provocative, but thoughtful. Many neocon hawks ARE Jewish." Nor is this the only time that Plame has retweeted other nonsense from the bigoted platform this piece came from – a platform of which she has pleaded ignorance. According to journalist Yashar Ali, Plame has tweeted at least eight other articles from the same website since 2014. Sounds like she is into some strange websites.

I actually read the Philip Giraldi article before I was aware of the Plame tweet. I read it on a neo-Nazi website, where Giraldi's articles are frequently featured. That's where Giraldi's articles belong – on overtly anti-Semitic and neo-Nazi websites. For Plame, a former CIA operative, to claim that she was unaware of the anti-Semitic content of Giraldi's article is to blink reality.

Plame had to know what she was doing, since she was aware of Giraldi's bigotry. Her apologies ring hollow. Her true feelings were revealed in what she said before she realized that she would be widely condemned for her original retweet. She must now do more than apologize. She must explain how she came upon the article. Who sent it to her? Does she regularly read that bigoted website? Why is she reading and retweeting a known anti-Semite? What are her own personal views regarding the content of the Giraldi's article?

The Plame incident reflects a broader problem about which I have written. There is a growing tolerance for anti-Semitism. Even when some people themselves do not harbor these feelings, they are willing to support those who do, as long as the anti-Semites are on their side of the political spectrum. This is an unacceptable approach, especially in the post-Holocaust era. Unfortunately, Valerie Plame is the poster child for this growing tolerance of anti-Semitism. She must be called out on it, as must others who follow the same path of bigotry.

The problem exists both on the hard-right and the hard-left. Both extremist groups see the world in racial, ethnic, and religious terms. Both engage in identity politics: The hard-left gives more weight to the views of certain minorities, while the hard-right gives less weight to the views of these same minorities. Both are equally guilty of reductionism and stereotyping. Neither group is prepared to judge individuals on their individual merits and demerits. Both insist on judging entire groups and of stereotyping.

American Jews, like other Americans, are deeply divided on important issues, such as the Iran deal, the current prospects for peace between the Israelis and Palestinians, and the Trump administration's foreign policies. To generalize about "Jews" is both factually and morally wrong.

What the hard-right and hard-left share in common is special bigotry toward Jews: The neo-Nazi right hates the Jewish people, and the hard-left hates the nation state of the Jewish people and those Jews who support it. Both views are bigoted and must not become acceptable among centrist liberals and conservatives.

Alan Dershowitz (@AlanDersh) is a contributor to the Washington Examiner's Beltway Confidential blog. He is the Felix Frankfurter Professor of Law, Emeritus, at Harvard Law School and author of "Trumped up! How Criminalizing Politics is Dangerous to Democracy."

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