BTW Anders, I am an American, proudly, and Thus I only fluently speak English, once spoke fluent Spanish (Mexican version) and dabbled in Swiss German for necessity. My guess is that German is not your first language.
Why? I find German speakers to be the most polite language users in the world. If they speak your language, they will only deviate to German when a colleague needs help translating. Most all speak English, usually fluently, unless uneducated. They will not exploit the American language weakness in my opinion as other Europeans frequently do. It is fun to be with an Englishman in those settings, because they often understand your language but will only speak English so you may not be aware. We native English speakers are quite stubborn about our language.