Yes but throughout time for most of history the leaders of a Nation were typically a part of the same ethnic group.
In rare case such as how Joseph ruled over Egypt but Egyptians are a Semitic Group, and Israelites are also Semitic group, however The Pharaoh still ruled over his Nation.
In The Case of The United States an African can rule over an Asian, or a German can rule over an Arab, or an Desi Asian can rule over an indigenous group of The America's.