What criticism was Tocqueville making about the expansion of U. S. democracy? Is his criticism valid?

Alexis de Tocqueville was the first French critic of democracy of the United States of America. He was best known for his work, Democracy in America. It was published after his travels from United States.

He thought that United States offered the most advanced example of equality because people can have their own individuality. However, because of their democracy, he believed that this will cause tyranny of the majority in which the majority will rule and can place their own interest at the expense of the minority. This will results in oppression of the minority group.