Here is a good, basic piece on the fantasy of the white race. The term Caucasian was created to trace the origin of “white” people to the Golden Age of Greece and the ancient Near East. These populations were not, of course, “white,” and this “Caucasian” race is an invention.
Americans were strong and vital because they were a mixture of different northern European nationalities, and as I have been reading elsewhere, whiteness as this kind of melting pot was truly consolidated in the 1920s … interestingly enough, the era of négritude and many other kinds of cultural nationalism. Latin America wants to be a brown mixture and the United States a white one, yet still a mixture. This is very interesting indeed.
A telling detail: Crèvecoeur’s 1781 text implies that the invention of [whiteness] confers upon the American a “new rank”. The American is a border-crosser and transcends narrow European nationalities. He has also closed ranks with other people deemed white, and has a government that responds to whiteness and not to noble lineages. This, too, is very interesting.
Axé.
coldhearted scientist وداد 
Being defined as white is important. There is the phenomenon of “passing” for instance. I am highly aware of my whiteness, living in an Asian majority setting.