In order to have a successful democracy, universal education is a necessity. So, teachers play a profound role in a democracy. They must educate students to be knowledgeable, questioning, and engaged participants in a democracy or democracy fails.
Without knowledgeable voters, a democracy cannot work. If we are choosing leaders without any knowledge to back us up, we are choosing poorly. In today's world, government leaders are called upon to make many different kinds of decisions, about technology, about science, about education, just as a few examples. We want the very best leaders to make these decisions, and if we have no knowledge, we cannot possibly assess whether or not we are making good choices in leadership. Teachers are there to provide us with as much knowledge as possible.
A democracy requires a citizenry that is questioning. This is an aspect of critical thinking that we want all teachers to impart to students, since we should never unquestioningly follow any leader or we are a nation of sheep. A democracy cannot survive if no one questions it. The great progressions of United States democracy, integration and the equality of women, as just two examples, have happened because people questioned the status quo. Without teachers helping students to see the power of questioning and encouraging way of thinking, there would be no progress at all, and we would not have a true democracy.
Teachers should promote engagement in a democracy, by teaching students how democracy works and how important their role is in it. Students who have no understanding of how the democracy functions are unlikely to become engaged citizens who vote. It is through this understanding that we become engaged in the process.
Universal education is the very foundation upon which a democracy rests. Without teachers to guide in knowledge, questioning, and engagement, a democracy can cease to exist.