why teach about the holocaust?

[from the “for educators” section of the US Holocaust Memorial Museum web site:]

The Holocaust provides one of the most effective subjects for an examination of basic moral issues. Through a study of these topics, students come to realize that:

The Holocaust was a watershed event, not only in the twentieth century but also in the entire course of human history.
Study of the Holocaust assists students in developing an understanding of the roots and ramifications of prejudice, racism, and stereotyping in any society.
The Holocaust provides a context for exploring the dangers of remaining silent, apathetic, and indifferent in the face of the oppression of others.
Democratic institutions and values are not automatically sustained, but need to be appreciated, nurtured, and protected; democracy is fragile.
Silence and indifference to the suffering of others, or to the infringement of civil rights in any society can-however unintentionally- perpetuate the problems.
A study of these topics helps students to think about the use and abuse of power, and the roles and responsibilities of individuals, organizations, and nations when confronted with civil rights violations and/or policies of genocide.
The Holocaust was not an accident in history-it occurred because individuals, organizations, and governments made choices that not only legalized discrimination but also allowed prejudice, hatred, and ultimately, mass murder, to occur.
Thinking about these events can help students to develop an awareness of the value of pluralism and encourages acceptance of diversity in a pluralistic society.
Holocaust history demonstrates how a modern nation can utilize its technological expertise and bureaucratic infrastructure to implement destructive policies ranging from social engineering to genocide.
As students gain insight into the many historical, social, religious, political, and economic factors that cumulatively resulted in the Holocaust, they gain awareness of the complexity of the subject and a perspective on how a convergence of factors can contribute to the disintegration of democratic values. Students come to understand that it is the responsibility of citizens in any society to learn to identify danger signals, and to know when to react to prevent genocide and the steps that may lead to it.