WHICH WORDS SPARK
One can estimate the likelihood that speech will spark violence in any given situation using just these five criteria: the speaker, the audience, the speech itself, the social and historical context, and the means of dissemination.
In each case, one or more of these criteria may be especially important. A speaker can have great influence over a particular audience, while certain audiences may be especially vulnerable, because of economic hardship, fear, or existing grievances. Certain language-related events—defined broadly to include such acts of expression as burning a book—can be particularly powerful. "