William Prince of Wales and Kate Middleton were married earlier today. Kate was given the title Dutchess of Cambridge. Despite the fact that the Cambridge in question is clearly Cambridge, England, home of one of England's two most esteemed universities, I imagine that my brother who works in Cambridge, Massachusetts will see this as a positive omen, while my father, who lives in Oxford, Ohio may be less impressed. ;)
The U.S. Constitution has a fair amount to say about titles on nobility, none of it positive:
Article I, Section 9 provides, in the pertinent part, that "No title of nobility shall be granted by the United States, and no person holding any office of profit or trust under them shall, without the consent of congress, accept any present, emolument, office, or title, of any kind whatever, from any king, prince, or foreign state."
Article I, Section 10 provides, in the pertinent part, that "No state shall . . . grant any title of nobility."
Article IV, Section 4 provides, in the pertinent part, that "The United States shall guarantee to every state in this Union a republican form of government[.]"