Presidents and other political activists learned long ago the power of public speaking. To convince people to do something, people need to have a strong emotional argument. They also need to make their argument in a way that sounds convincing.

Before television, people would listen to political leaders on the radio, watch fifteen minutes of news before a movie, or read their speeches in the newspaper. With television, political leaders now had to worry about how their message looked to an audience.

The Power of Public Speaking