There's plenty in there that isn't about culture, but it's hard to parse TFA without at least skimming over the definitions of Realism, Liberalism and Constructivism.
My personal view, from someone who studied International Relations in undergrad: at the end of the day, these are all just conjectures with few real-world implications. Basically a bunch of academics trying to one up each other with the most creative, elegant and innovative model of how States operate and what drives foreign policy, despite the fact that virtually none of them have ever been in a room where the real meaningful foreign policy decisions are made, and with a very myopic view on the role that Economics / Business / Psychology shape international relations.
I always liked this quote about policymaking:
"This is the most pervasive of of all Washington legends: that politicians in Washington are ceaselessly, ruthlessly, effectively scheming. That everything that happens fits into somebody’s plan. It doesn’t. Maybe it started out with a scheme, but soon enough everyone is, at best, reacting, and at worst, failing to react, and always, always they're doing it with less information than they need.
That's been a key lesson I’ve learned working as a reporter and political observer in Washington: No one can carry out complicated plans. All parties and groups are fractious and bumbling. But everyone always thinks everyone else is efficiently and ruthlessly implementing long-term schemes."
I'm sure it's not a small circle of shadowy people that only meet at 2am and require a heavily sedated black cat for each participant, but there are plans and decisions, and actions carried out that commit the country to tens or hundreds of billions of dollars and military involvement measured in decades. Those aren't "oh gosh, what's this now? well, put some duct tape on it, I suppose" reactions.
Even a decision to go to war is full of uncertainty. Iraq I was days, Iraq II was decades. A general can never promise you it will come out one of those ways or the other.
Maybe I'm wrong though. It'd at least be nice to imagine someone has a plan and that it's not all just organic chaos.
"The Thick of It" does a good job explaining my side though -- it almost feels like a documentary for policy circles. The environment at that level is unbelievably frenetic. Getting anything done with intention is a near miracle.
But you're probably right that sometimes, at least on rare occasions, important people are able to clear off enough space to make important things happen that are long lasting with intention. I just think it's the exception, not the rule.
Biological theories - in such theories biology is key factor. For example: scientific racism (Arthur de Gobineau), Social Darwinism (Herbert Spencer), or theories where you treat civilisations like a living organism that always have to go through 3 phases: youth/development, adulthood/prosperity, senility/decline (for example Oswald Spengler theory).
Economical theories - economy as key factor. For example: Liberalism, Marxism, etc. Right now those theories are very popular, a lot of people assume that there is actually one big human civilisation and differences are just in economic level of each country/region/group.
Ideological theories - ideology/religion as key factor. Examples: Christianity, Islam, Freemasonry, Cultural Marxism, etc.
There were also attempts to merge all of those aspects: Toynbee, Koneczny (someone mention his work in one of the comments), Huntington (personally I think he ineptly copied Koneczny work).
Because of Pax Americana after WWII most people start belive that liberal democracy and capitalism was finall destination of all civilisations (Fukuyama famous book: "End of history"). But right now with rise of China and their model of state/economy/politics people start looking for much broader theories.
For what it's worth, unlike Christianity, Islam, Freemasonry, etc. there is no such thing as 'cultural marxism'. The modern usage seems to be as a catch-all term used by (literal) fascists and fascist-associated groups for literally any progressive or postmodern viewpoint, but in addition usually has the connotations of 'cultural perversion' and 'conspiracy'. Prior usage seems to be to describe an anti-semitic conspiracy theory (that is in part related to modern usage), and the term as a whole dates back to when it was coined by the German Nazi Party ("Cultural Bolshevism" - Kulturbolschewismus) to describe modernist art movements that they thought were 'degenerative'.
Rational Wiki's second description is incredibly descriptive:
""""Cultural Marxism" (both uppercase) is a common snarl word used to paint anyone with progressive tendencies as a secret Communist. The term alludes to a conspiracy theory in which sinister left-wingers have infiltrated media, academia, and science and are engaged in a decades-long plot to undermine Western culture. Some variants of the conspiracy allege that basically all of modern social liberalism is, in fact, a Communist front group."""
See:
https://rationalwiki.org/wiki/Cultural_Marxism
https://en.wikipedia.org/wiki/Frankfurt_School#Cultural_Marx...
My point wasn't that Marxism as a whole does not exist, as you seem to have replied. My point was that "Cultural Marxism" specifically does not exist, and is literally neo-nazi propaganda.