The social media site Twitter offers an extraordinary form of communication. But perhaps because of its scope and anonymity, it is also a hotbed of racism, bigotry and anti-Semitism. This has never been clearer than in the wake of Senator Chuck Schumer’s announcement that he will oppose President Barack Obama’s nuclear deal with Iran.In doing so, Schumer became guilty of heresy in the eyes of many on the progressive Left and the isolationist Right. The former is now campaigning against Schumer’s ascension to Senate Minority Leader.After reading an article mentioning the subject by writer Lee Smith, I waded into the cesspool created by the popular Twitter hashtag #Dump- Schumer. What I found was a deluge of anti-Semitic vitriol. By Saturday I had accumulated a collection of well over 100 tweets from both Left and Right attacking Schumer as a paid agent of Israel or AIPAC, a puppet of Prime Minister Benjamin Netanyahu and an outright traitor to the United States, loyal only to Judaism and the Jewish state.Many in the #DumpSchumer ranks appear to believe that the senator is, as one tweeter put it, “an Israeli TRAITOR Jew.” Another proclaimed that Schumer is “a traitor to his own country which is the US NOT ISRAEL.” Another asserted, “Calling Schumer a traitor is just telling the truth. He’s not one of us – his only loyalty is to Jews.” Another echoed this, saying, “Schumer is only loyal to his tribe... certainly not to America.” Another was somewhat more subtle, declaring, “A senator is there to do the right thing for country [sic]. Question is which country is he thinking Abt?” Another asked, “Will the Senator From Israel Yield the Floor?” Another declared, “He’ll make even More $$$ as official #AIPACLobbyist.”Another stated, “Schumer is doing the bidding of AIPAC.” Still another simply called the senator “The Israeli Manchurian candidate.”Echoing rhetoric that has a distinctly dark provenance, other tweeters more or less advocated Schumer’s deportation to Israel.One said so plainly. Another question, directed at Schumer himself, asked, “If you prefer ISRAEL over the USA? Why not move there?” There were also pieces of ostensibly more respectable provenance.Journalist M. J. Rosenberg remarked, “It is sick that most Jewish members of Congress will decide on #irandeal based on Israel’s interests not US.” In more insidious fashion, Josh Marshall of Talking Points Memo asked, “So why did Schumer oppose the deal? I think he moves in circles, personal and financial, where this deal is simply anathema.”One is left to wonder which “personal and financial” circles these might be. For many, the evil standing behind Schumer was clear: Netanyahu. One tweet referred to Schumer as “Bibi’s US Senator from Israel.”Naturally, all of these tweeters refused to acknowledge even the possibility that they were engaging in anti-Semitic rhetoric. A picture making the rounds told Schumer, with breathtaking cognitive dissonance, “Calling out your allegiance to Israel ... is not anti-Semitism.”Awakened by all this were more forthright characters. That is, neo-Nazis. Crawling out of the virtual woodwork, one proclaimed, with the concision of Conrad’s Kurtz, “Exterminate the parasite!” Another howled, “International Jews are the cancer of the earth! Sign this petition to arrest Netanyahu!” referring to a campaign to have the prime minister arrested for war crimes during an upcoming visit to Britain.This is a small sample, but it is representative enough.But the final tweet cited above did prompt an interesting realization.Here was a proclamation of genocidal neo-Nazi racism coupled with an anti-Israel petition from the ostensibly anti-racist Left. It seems that politics is indeed circular; its extremes always converge in the end, especially when anti-Semitism is involved. There appears to be something in it that satisfies all emotional desires and answers all questions. Hence its great appeal to both sides of the political spectrum.Indeed, during my exploration of the #DumpSchumer tweets, I was twice called a “kike” by neo-Nazis, and once a “semitic bigot” by a Leftist.Now, it seems, these two sides have come together around the person of Senator Schumer.Unfortunately, this convergence is not new. During last summer’s Gaza War, I was inundated with anti-Semitic statements from reactionary Muslims, Leftists, neo-Nazis and most everyone in between.And lest we forget, this was merely a tiny symptom of a much larger and far more dangerous phenomenon.Throughout Europe and elsewhere, there was an explosion of anti-Semitic rhetoric and physical violence.This climaxed most famously in France, where a synagogue was attacked and a Jewish neighborhood trashed by rampaging mobs, followed by the Hyper Cacher massacre.I have called this phenomenon the “Global Pogrom.” But thus far, it has mostly been a European pogrom.In the United States, it is mostly confined to college campuses. If the anti-Semitism of the #DumpSchumer virtual mob indicates anything, however, it is that the pogrom is now centered on a specifically American issue: The Iran deal and its opponents.This, in turn, demands that we entertain the possibility that the disease has now reached the United States, and is finally erupting into the public sphere.If this is indeed the case, I think it very likely that this is only the tip of the iceberg. Certainly, if a senior US senator can so quickly become the target of a widespread campaign of anti-Semitism from both the Right and the Left, we should all increase our vigilance. The lights have gone out all over Europe. We must ensure that they remain lit in the United States.The author is the associate editor of Tower Magazine.