This is a topic which has had so much written about it that you could fill an entire city library with books entirely dedicated to this topic. Marx took a shot at it. As did Sartre. There were, of course, also plenty of good books written on this topic, but rather than list them all, I want to suggest a few simple common sense points and then go to what I consider an authoritative explanation of this thing we call “antisemitism” and which, of course, has nothing to do with Semites.
So first, let’s dump this silly term and replace it by a simple and straightforward one: judeophobia. Just like any other phobia (say, for example, russophobia) the phobia of X is the 1) fear and/or hatred of X. Some people hate Jews, others fear them (think of the “fear of the Jews” in the Scripture), some do both. So judeophobia seems both logical and uncontroversial to me.
Second, it is a truism to say that everything in the universe has a cause. That includes phobias. Including russophobia and judeophobia. For example, I would be the first person to admit that there are objective characteristics of the Russian people which makes other people fear and hate them. Like the fact that all western attempts at conquering Russia have failed. Or that the Russians have always, and still are, rejecting the Papacy. Just these two factors will create plenty of russophobia in the West, for sure.
So, the next thing we can ask ourselves is what is it in Jews which causes judeophobia. Alas, before I look into this, I need to clarify a number of assumptions I make.
The first one is that Jews are not a race or ethnicity. To prove that, I defer to Shlomo Sand’s book “The Invention of the Jewish People”. As I explained elsewhere, Jews are a tribe: A group one can chose to join (Elizabeth Taylor) or leave (Gilad Atzmon). In other words, I see “Jewishness” as a culture, or ideology, or education or any other number of things, but not something rooted in biology. However, I also fully agree with Atzmon when he says that Jews are not a race, but that Jewish culture/politics/ideology is racist (more about that later).
Next, there is also what is commonly known as “Judaism”. That, by the way, is also a misnomer, at least if by “Judaism” you refer the faith of the Old Testament, the faith of the Ancient Israel, the “God of Abraham, Isaac, and Jacob, the God of our forefathers”. Modern “Judaism” which was created well after the destruction of the Temple in Jerusalem in 70AD. Modern “Judaism” ought be to called “Pharisaic Talmudism” and its true creators are Shimon bar Yochia, Maimonides (aka “Rambam” in the video below), Joseph Karo and Isaac Luria. The reason why this religion ought to be referred to as Pharisaic Talmudism is modern Judaism is the continuation of the sect of the Pharisees (the only Jewish sect which survived the destruction of Jerusalem and of the Temple – all modern forms of “Judaism” trace their roots to the Pharisees) and that it’s main source of authority is the Talmud, a collection of writings based on the ideas of the sect of the Pharisees and complied from the beginning of the 2nd century. To separate them from non-religious Jews, some authors have offered the term “Judaic” to describe a person adhering to this faith. Seems reasonable to me.
Here is the key thing, while many modern Jews are non-religious and really members of a self-described Jewish tribe, there is no such thing in history as a “Jewish culture” distinct from Pharisaic Talmudism. Remember that national categories are recent creations from the 18th and 19th centuries. For most of history people defined them in reference to 1) their place of residence or birth 2) their religious affiliation and 3) the identity of the ruler they were subjects of. In contrast, nationality and ethnicity are largely modern concepts. The only thing common to a Jew from the Middle-East, Central Europe and North Africa would be teachings of Pharisaic Talmudism. It is only logical therefore to look at this unique common characteristic to try to identify the causes of the hatred and fear Jews have inspired pretty much everywhere they have ever resided.
I will use two official Jewish sources to ascertain the causes of antisemitism, first the Simon Wiesenthal Multi-Media Learning Center’s website and a lecture by Rabbi David Bar Hayim.
Here is what the Simon Wiesenthal Center writes on the page “Why The Jews? The Patterns of Persecution”