American History is much shorter than European history. Although Native Americans have lived in the Americas for thousands of years before Columbus arrived, written records and knowledge of events dates from about 1492 AD. Consequently, American history has less content to it, but it is no less rich than what occurred in Europe. In fact, greater changes have occurred in America relative to Europe in roughly the same time period.
The reasons for this are many: European civilization already had set institutions, traditions, customs, loyalties, and cultures, whereas the new American settlers had to develop these things on their own, having to adapt to different political and geographic realities, even as they were using European models for government, law, and culture. The result was a new form of civilization, one that quickly found itself mostly freed of the old bonds that characterized European society at the time, which enabled new ideas to flourish. From these ideas, Americans have gained such things as the Constitution, an entrepreneurial spirit, and an attitude marked by a belief in equality of opportunity. This contrasts greatly from Europe, which fluctuated between the extremes of opportunity for the privileged and a radical belief in equality of result.
As such, American history has been characterized by an individualistic spirit, the belief in limited government, and the defense of individual rights. These things are vital to any teaching of American history.