All Western democracies, including the U.S. and Germany, are seeing powerful protest movements against globalization and integration. They are agitating for a recapturing of control, or 'sovereignty,' and often also of ethnic homogeneity. Although they keep talking about the nation-state, they oppose key principles of Western constitutionalism like separation of powers and the protection of minorities against the tyranny of the majority. They want a tribalization of politics. That's something the Tea Party and the U.S. alt-right have in common with the AfD.