[crazygringo]

> Therefore, I don't see how "the Germans are speaking English" makes the point that language isn't DNA.

Because German isn't English. Speaking one doesn't let you understand the other in conversation, not even a little bit. They're not like e.g. Spanish and Portuguese.

The fact that English is Germanic is a historical fact about where it came from, what it evolved from a millennium ago. But only a small percentage of Germanic influence remains in modern-day English vocabulary. It doesn't have anything to do with Germans in the US learning English.

[DiogenesKynikos]

Most simple words in English are still Germanic in origin. In fact, in the previous sentence, I count six Germanic words (most, word, in, English, are, still), versus only three Latin/French words (simple, Germanic, origin).

But as you say, the relationship between English and German doesn't have anything to do with what we're discussing. English and German are two different languages. Immigrants who spoke German gave birth to children who learned English, and after a few generations, their descendants didn't speak German any more. And that didn't just happen with German immigrants. It happened with every non-English-speaking immigrant group.