I have to strongly disagree here. While it is definitely possible to teach greater/lesser ideologies, and it absolutely does happen, at their core, humans are social creatures prone to forming groups and passing biased judgements on out groups. In groups and out groups form, and competition starts, followed by the mud slinging. It’s not a training, it’s part of human nature. The teaching just accelerates things and pushes people into groups faster and with more vehemency.