Where is Diversity?

Today my teacher said that the culture in Pakistan is not a same one in every part of it. It has diversified cultures, there is not one language, not one religion, not one faith, not one dress, not same norms and values also. He added that the culture in America has not diversified cultures. In that time i was to say that, ” I am not agree with you” but i stopped myself and thought that “He is my teacher, may be my any word can against his thoughts. Now i can express here in my blog that there are many problems in America as well which are all related to their culture.