Emotions are the heavy artillery of influence and anger is one of the most potent emotions. For a good reason ancients described it as “a thing much sweeter than honey in the throat, it grows in the breast of men”. Anger comes first in Aristotle’s Rhetoric, followed by other emotions.
There are many ways that you can appeal to anger, but one of the best ways is to show people that your opponent has belittled them. This can be very effectively used in advocacy campaigns. (And it can be equally effectively used in political debates: world-class orators used this technique in debates since immemorial times). Needless to mention, use this technique with caution and compassion because when applied successfully it may induce in your opponents severe emotional suffering.
A good example how this can be used in an advocacy campaign comes from 1994 campaign against tobacco companies. California Department of Health Services, working with L.A. ad agency Asher/Gould, made two anti-smoking TV commercials. One of the ads, called “Nicotine Sound Bites”, showed an actual footage of a congressional hearing where chief executives of the four major tobacco companies testified under the oath that nicotine is not addictive; the ad ends with the question “Do they think we’re stupid?”
According to the authors of Tobacco War: Inside the California Battles, public health advocates loved the ad and the tobacco industry went berserk. The ad indeed might have been very effective because it implied that executives of tobacco companies have belittled the public. Yet, the ad did not have a chance to hit tobacco companies significantly: it was pulled off the air in less than three weeks when R.J. Reynolds threatened lawsuits. Perhaps tobacco industry’s response indicates that they themselves were afraid that the ad might succeed more than they could afford it.