Anglo-Saxons are responsible for feminism. Jews are responsible for the "third wave" variety that came to the fore in the 70s. Modernism wasn't invented by Jews, they just took it to the next level. Europeans undid themselves between the Renaissance and the Enlightenment (and feminism is a product of the Enlightenment, so it was originally an European creation), and sunk into a deep cultural decline in the 19th century which paved the way for the rise of secular Jewry as a cultural power, who went through something akin to their own Renaissance around that time (but are currently in a decline phase).
You just brought up another question, why are goyim governments so easily influenced by Jews. Money, corruption? I guess the conspiracy theory has the merit of being logically consistent. But it ignores too much data and reasons in a top-down way, not a bottom-up way.
Because Jews are a caste, not a race, and societies are dominated by those higher in the social hierarchy, always have and always will be. So the mechanism by which a small minority can control the majority is already in place in the very fabric of human nature itself, which is why Democracy is a sham and an illusion. The ruled cannot also be rulers, it's a contradiction of terms.
Now, the natural hierarchy of any society follows the order of the Hindu caste system. You can find the same exact structure in any traditional society, just not in such an explicit form, and Europe was no different. Medieval Europe was dominated by Church and State, which is to say, by the Brahmin and Kshatriya, like any other society that has ever existed. The balance between the two dominant classes was made official when Charlemagne prostrated to the Pope during his coronation as Holy emperor while in his turn the Pope prostrated at the feet of the newly elected emperor, which was a recognition of the superiority of each within their own domain. What happened is that this balance was completely shattered after the 1100s because of the incessant quarreling between the temporal authorities of Europe. The political chaos that resulted from the collapse of the Roman empire could not be corrected. Unlike in the Roman east, which enjoyed political stability for more than a thousand years, western Europe could not be unified under a single banner. Charlemagne came close, but his efforts came to nothing when his empire collapsed after his death. In the midst of this unrelenting political quarreling, the balance between the Church and the state was turned upside down as the state attempted to use the Church to further it's own political aims. The Church thus became a political entity, it's ranks being filled with political agents (the introduction of celibacy in the priesthood was a measure adopted to combat this trend of worldly people joining the ranks of the church to pursue a political agenda, something a lot of people don't realize).
In the midst of this chaos, a new class of rulers arose, the Vaishya, who came to the fore in full force between the 13th and 14th centuries, rising to ultimate power through out the Renaissance (which in many ways was their doing). We see in a Jakob Fugger the first case in which money, and not authority, became the real source of power in Europe. The kings and nobles of Europe became highly susceptible to the corruption of money lenders because war is expensive, and political domination became more and more important as the cultural and spiritual unity of Europe was torn apart by the rose of Protestantism.
Bereft of an unifying cultural ideal, and with a ruling class highly susceptible to bribery and corruption, Europe was easy prey to any external force capable of exploiting such weaknesses, which is how the Jews rose to power. Their alliance with the Protestants in particular is the reason why Jews are usually to be found whenever Protestantism dominates. It is very characteristic that the two most powerful men at the turn of the 20th century were Rockefeller and Rothschild, a Protestant and a Jew.
With all this said, it remains to explain why Jewish influence has such a "nefarious" connotation, because ethnic groups rising to power is neither new nor particularly special. Why are Jews singled out so much, compared to other groups that came into domination at one point or another? The secret to the so called "Jewish" question is that Jewishness as a cultural identity became associated with revolution. I came across this idea originally when i read Weininger, who accused the Jews (Weininger was Jewish btw) of "smirking at the Good". The Good of course means the formal order of the universe, that which in Christianity is associated with Christ himself, who is the incarnation of the eternal Logos, which is the Good precisely. So the origin of the Jew as revolutionary came about when they rejected Christ. Revolution is not inherent in the Jewish race itself, as the Nazis believed but also as someone like Kevin McDonald, who is neither a Nazi nor an evil person in general, believes, because this is the obvious conclusion of anyone who accepts evolutionary explanations as the basis of all human behavior.
The truth is that Jewish identity is only related to race in an indirect way (Semites are different from Aryans but this difference has nothing to do with whether one is decadent or not), and is mostly based on a spiritual crisis which resulted from their rejection of Christ. This idea was expanded fully by E. Micheal Jones, who wrote a whole book on the spread of revolutionary ideas in Europe at the hands of Jews:
In essence, Jewish identity after the advent of Christ and the destruction of the temple by the hands of the Romans became infused with revolutionary ideas on one hand, and an hatred of Christianity on the other, so that the issue is not a racial one (race plays a role but it's not a decisive factor), but a cultural/spiritual one. Indeed, Jones is quickly to point out that the issue cannot be a racial one, given that Christ and the apostles... were Jews.
Now, the issue becomes even more complicated because of two things. First, because like i said Jews are a caste, not a race per-se, and Judaism itself was a Brahmanical religion. The superiority of the Israelites vis the gentiles which is a continuous refrain in the old Testament was a spiritual one, not a racial one as it became at the time of Christ, as Jews begun to interpret their texts literally rather than spiritually. The fact Jews are a caste is important because it explains not their intellectual prowess in itself but their influence as an intellectual entity. This is how Jewish "thought" conquered our own intellectual class, especially since individuals tend to put caste before race, so that a "white" intellectual is more prone to mingle with a Jewish intellectual than a white peasant.
But the second issue is that, because of their revolutionary tendencies (which were kept in check by whatever of their religion remained uncorrupted, a block which was lifted when Jews became secular), and their view of themselves as the "other" (Jews in the middle ages kept referring to their Christian neighbors as "Egyptians", and the story of Joseph goes a long way in explaining the role Jews took in medieval Christian society) means that Jews started to channel elements of a different caste, that of the Pariahs. Thus, Jews became a sort of Brahmanical/Pariah hybrid, so that their intellectual influence started to spread among those elements of society which were disaffected with the social order, thus building alliances on everything in western society which was against the dominant culture, which is where we are at today.
Lastly, there is a more esoteric, mystical side to all this in that Jews possessed an ancient esoteric tradition which also became corrupt through out the centuries following the destruction of the temple, but most mostly during the late middle ages. The most well known branch of this tradition is the Kabbalah. If you red Guenon at all, you'll know that modern culture is actually the product of an "inverted" esoterism, perpetrated, quite consciously, by a class of people belonging to what he termed as a "counter-initiation". Now, if one looks at the situation in Europe at the end of the middle ages, one sees that there are many aberrant "esoteric" syncretistic trends popping up everywhere, from sources which are not at all Jewish (Rosicrucianism, neo-Platonism, Freemansory etc) but which also included Jewish Kabbalah. I believe that this counter-initiation group Guenon was talking about was a product of this Gnostic-like eruption of esoteric syncretism, so on top of the oligarchic rule that dominates western society, there is this satanic world view being pursued by an intellectual elite mired in this inverted esoterism which is NOT purely of Jewish origin but in which Jews played a dominant role between the end of the 19th century and 20th century, which is why it is associated with them alone.
And so here we are. In all of this it is important to remember one important thing, in that Jews did not invent modernity nor are they the artificers of the demise of western culture, for if that was the case, one would have to simply declare Jews superior. The truth is that Europeans destroyed themselves first and Jews were just there to take advantage of the situation. But the most important thing is to understand that the type of decadence Jews pushed on the west during the last centuries is not "Jewish" in itself, it just found in Judaism an appropriate agent. If you took Jews out of the picture, this type of decadence would have just found another channel. Europeans themselves were moving towards that path on their own anyway. The forerunner to Schoenberg was Wagner etc. The most idiotic idea white nationalists entertain is the notion that without Jews or other ethnic groups, the west would have succeeded in creative an earthly utopia and that every single problem facing the west today is due to Jews and Jews alone, which is just an absurdity. The Greeks were going towards the same direction before they got conquered by the Romans. Were the Greeks also corrupted by the Jews?