While Angela Merkel, Germany’s chancellor, was enjoying the hospitality of President George W. Bush at his ranch in Crawford, Texas, recently, a German town was busy with its own transatlantic diplomacy.

Dustin Byers, a 20-year-old student from Oregon, was making a guest appearance at Helmut Brake’s English class at the Otto-Hahn Gymnasium in Nagold, where he had been invited to talk about US foreign policy.