I think Joseph Goebels was in agreement with you when  uttered, "A lie, repeated often enough, becomes the truth."  As for demonization of political enemies, it can be called peer pressure and, ironically, is effective in smaller, tightly knit, communities and villages. My example was inspired by a page in the Wall Street Journal. On the left column, the subject was bumps in the road of China trade. The right column was sub-headed, "Weaknesses in the American Economy."  I am trained to notice how newspaper editors compose for effect.