There have been gains made by anarchist movements. Much of the major retreats the IMF took in the early 2000s were the direct result of the Direct Action Network, for example. Anarchists were majorly involved in Occupy (a radical mass moment that, i.m.o. because of the lack of a vanguard party, petered out). Long-term sustainability and viability is what they lack. They have had lasting gains in capitalist states (the 8 hour day, etc.), they have had revolutions, but after the revolution starts they can't seem to stick it out.

The important thing about being a communist is about not pontificating on the true spirit of this person or that group. You look at material things you aim to do and see who is against you and for you on an issue by issue basis as you build worker power. Spending time wondering what the true nature of an ideology's followers is is idealism.

the US security state funded a bunch of anarchists in the 1960s because they aren't a threat to state power and were an effective way to split the left against MLs

Anyway, the basic point is that socialist revolution is neither easy (as the Trotskyists and ultraleftists would have it) nor impossible (as the liberals and conservatives would have it), but hard. It will require dedication and sacrifice and it won’t be won in a day. Tankies are those people who think the millions of communists who fought and died for socialism in the twentieth century weren’t evil, dupes, or wasting their time, but people to whom we owe a great deal and who can still teach us a lot.

Or, to put it another way: socialism has powerful enemies. Those enemies don’t care how you feel about Marx or Makhno or Deleuze or communism in the abstract, they care about your feelings towards FARC, the Naxals, Cuba, DPRK, etc. They care about your position with respect to states and contenders-for-statehood, and how likely you are to try and emulate them. They are not worried about the molecular and the rhizomatic because they know that those things can be brought back into line by the application of force. It’s their monopoly on force that they are primarily concerned to protect. When you desert real socialism in favor of ideal socialism, the kind that never took up arms against anybody, you’re doing them a favor.

from https://redsails.org/tankies/

They are not a threat. At most they are a mild nuisance. Like Trotskyists, their main function is as a tool for preventing the formation of real and effective revolutionary movements.

Riddle me this General, have you seen major anarchist movements in the Global South, mainly against U.S and Western imperialism?

If you know, ye know...

Food Not Bombs gets regularly harassed by police.

It is easier to evade attention by either not engaging in praxis, or doing so in a decentralized manner.