My comment on Bonald’s post:
Leftism is the logical conclusion of liberalism (or at least, it most easily follows). Back when there were still conservatives, there could still be serious intellectual resistance to leftism. But now, instead of conservatives, we have right-liberals. They make stupid arguments for conservative causes, which arguments are all based on liberal principles. Their effect is not to slow down the leftist idea, the only thing slowing it down is natural common repulsion, their effect is to distract those who are so repulsed, since without right-liberal distraction, those so repulsed might discover conservatism. They’ll do this until social acceptance of the idea is set in stone, then they’ll move on. It becomes set in stone once a generation is raised to adulthood accepting it, which goes to your second point. I think the reason why most young people tend to embrace leftism, is because young people tend to be more susceptible to outrage. And leftists are the only side allowed to express outrage, thus young people tend to go left.