I think that, aside from the preliminary part I discussed earlier in this thread, there's also a case to be made linking some economic ideas that have not been put to rest yet to conspiracy theories. I've been rehashing lately a lot on alt-right, trying to better discern their side of the argument and more and more I get the idea that their main argument on population is based on economics, not demographics. Take for example
Malthusian economics, a theory presenting 'preventive' and 'positive' checks as part of a population control schema fearing that the introduction of greater population than what's necessary in place will deplete the finite resources of that location, leading to destruction, war and death.
This is an idea widely disproved for at least two hundred years now, especially with the mechanization process that allows for exponentially greater production of good, services and foodstuff necessary for the widening of the population, as well as due to the fact that when presenting populations to different environments their reproduction strategies alter - thus presenting the same plateau as the majority population.
Yet, Malthus hasn't been put to rest.
I'm going to use a cultural reference to make the example of how Malthus' idea of population control could be tied to terrorist acts, and I am going to use an example all of us have seen already but probably missed. I know many will roll their eyes to that, but it's late here and I am tired. So, deal with it.
Thanos, dudes. His plan was to eradicate half of the population on the universe, not out of hate according to him, but out of necessity to preserve life as everyone knows it. Thanos acts under the principles of Malthusian economics, thinking that overpopulation is bound to lead to devastation, famine and death. So, he takes it on himself to 'spare' those he disappears, and 'save' those who will remain. The only thing that doesn't really make the connection so obvious is Thanos' insistence on a balanced system, where everyone get a 50/50 chance to survive.
I think the question why do they hate is beyond the point. It seems more likely that the people targeted are simply seen as more expendables on the eyes of their attackers, since they are at the bottom of the totem pole. I may be rambling here, but do you think we ought to seek some answers to theories such as these?