Anon defined the 'Frankfurt School' as
a group of communists in Germany of the 1930's who woke up to the fact that the masses were not behaving on cue, despite the worsening economic situation. They decided Marxism needed updating and essentially advocated a change from the crude, stupid economic rhetoric to the more subtle and effective machinations designed to infiltrate the bastions of Western Culture, ie the family, the media and the Academe.I think anon is wrong in defining the phenomenon as a conspiracy. Reality is more complex. There was never a "Frankfort School" as such, only a diffuse philosophical movement or environment. (I was corrected by anon.: There was a formal academic institution called the Frankfurt School, with paid researchers and a modernist concrete building. This being a Learning Diary, I thank those who improve me so I can learn from my mistakes.). When it sprouted "Cultural Marxism", it was rejected and combatted by all Communist Parties in the world. This ideological environment of Pre-WW2 Central European intelligentzia affected also the National Socialist movement (which had much ideological affinity with the German Communist Party).
Curiously, the Nazis did not find this to their taste (J's Comment: I disagree. The National Socialist movement - which was Socialist and Marxist ! - also moved within the general revolutionary intellectual environment of Pre-WW2 Central Europe. It was only the Jewish intellectuals who had to leave Germany, and not because of their ideas but because they were Jews. Most found refuge in Palestine, only a few succeeded in immigrating to the USA)..., so most of them escaped to the US where they conned the unsuspecting locals into extending a charitable welcome; especially, I believe, in a particular university in New York.
Once esconced in the comfort and security of the US, they set about destroying it, and the West in general, with what they describe as "The long march through the institutions". This has resulted in what is known today as "Cultural Marxism:, also known as "Political Correctness".
Among the many perfidies they promulgate can be included the trashing of the nuclear family; open borders; indoctrination of the young; undermining free speech rights; the ridicule of white identity while actively promoting other ethnic identities in opposition to whites; feminism; erosion of public morals; humiliation and weakness of western countries; large scale guilt-mongering; and on and on.
Most of the German Jewish intellectuals did not move to the USA (they couldnt, because of America's strict quotas against Jewish refugees) but to Palestine. Here they had no influence at all, except maybe in architecture. Intellectually and politically they were erased by the very hard Zionist Left that dominated the Sochnut (a pre-State forerunner of the Israeli government) that had no time for philosophical elucubrations of the despised "yekkes". Eventually, Israeli left (aka the labour party) adopted the Political Correctness doctrine, but not because the post-mortem influence of the yekkes but because of its aping the Americans. Heaven is mercyful and the rotten Israeli Left has been displaced by the political line of Vladimir Jabotinsky. Should these people (widely called the Likud) go soft, a harder movement is already waiting at the wings to take their place. They are the religious zionists, Mizrahi, whose youth is spearheading the Jewish settlement in Samaria. Should they spoil (I see signs of it - many embrace the Earth aka "organic" and "green" holisticism), then the hard core (pic) will crawl out of the crevices and lead the nation. A step further to the right, impatient, are those who are working on bringing the Messiah (I am not kidding). They go by the Bible. Literally. It is not the Jews that keep the Shabbath, the Shabbath (the Bible) keeps the Jewish people.