“The more you can increase the fear of drugs and crime and welfare mothers and immigrants and aliens and poverty and all sorts of things, the more you control people. Make them hate each other. Be frightened of each other and think that the other is stealing from them. If you do that you can control people.” – Noam Chomsky
Add in terrorists, guns, food, chemicals, strangers, climate change (thanks Kevin), and corporations, and you get nearly everything our politicians use to control us.