I'm not sure either. I try to find answers in an available literature. This piece is written by an American Jew so I have no choice but assume that he's not an antisemite.
In the early 1990s, University of Iowa journalism professor Stephen Bloom, feeling alienated in Iowa City, went searching for his Jewish heritage. He thought he could find it in Postville, a small town in northeast Iowa, where he discovered there was an enclave of ultra-Orthodox Jews. This book, framed as both personal journey and examination of cultural clashes in the American experiment of multiculturalism, documents what became his profound shock, and disappointment. In looking for romantic myths and legends of the Jewish past, he found instead a jarring ghost from Jewish history and traditional identity that deeply troubled him.Postville A Clash of Cultures in Heartland America, by Stephen G. Bloom,The story centers upon (...) Chabad Lubavitcher Hasids ("the pious") who in 1987 bought a slaughterhouse in Postville (population: about 1,400), imported hundreds of non-Jewish illegal alien laborers to work for $6 an hour in oppressive conditons, and, since then, have been taking over the town. They also bring pollution to the local river, at least two attempted murders, and Iowa state lawsuits against the company. Bloom hears such tales first from angry local non-Jewish townspeople and initally assumes that their perspective is merely an expression of anti-Jewish prejudice. The longer the author spends in the town, however, and the more he time he spends with the ultra-Orthodox Jews who seek to pull him into their community, the more he accepts the fact that it is not "anti-Semitism" that fuels the outrage felt by longtime Postville residents, but verifiable Jewish hostility, discrimination, and exploitation of non-Jews. A range of classical "anti-Semitic" canards against the ultra-Orthodox Bloom finds to be true. "Many of the Hasidim I had encountered in Postville pretended to be holy," writes Bloom, "but their actions displayed bigotry and racism of the worst degree. (...) This book is a must read for anyone who seeks to honestly understand the verifiable origins of what is popularly known as "anti-Semitism".
As you can see, von Bismarck, all you need is a 1000 Postvilles plus a 1000 years of history and here you have it: a hatred.
We're lucky the US is a very young country and that there is not too many unwashed peasants.
You assume wrong. Some of the worst "anti-Semites" (or rather, Jew haters) are secular Jews who hate the religious. This man Bloom, a self-described atheist and secular Jew, set out to demonize the community of religious Jews, and he gets away with it because of people such as you who think it is impossible for a Jew to hate Jews, but there are certainly Jews who hate Judaism.
For other examples of Judaism-hating Jews, try Karl Marx, or any of the members of the "Peace Now" crowd.