They're "offended" because they speak German in private and not in public where English-speaking should be the norm. Both in America and in Germany, most people of German descent can speak both English and German properly. Americans are tired of Spanish-speakers either not even bothering to learn how to speak English or making people and organizations cater to them by speaking or writing in Spanish. Spanish-speakers should not be ordering food in Spanish; Spanish-speakers should not be sending their kids to school speaking Spanish and then forcing taxpayers to foot the bill to have translators or educational assistants speak for them or teach them English since they don't bother to learn it on their own; Spanish-speakers should not be coddled by having businesses or groups understand Spanish or create telephonic systems where you "press 2 for Espanol".

You're either not informed or willfully disingenous when you act like our modern day situation with Hispanics and Spanish-speakers is comparable to that of German immigrants coming to America over a hundred years ago. The former group feel entitled and don't bother to adapt or to learn English simply because everyone is too afraid and limp-wristed to tell them that they should. The latter group assimilated over time and bothered to learn the English language and switched between German and English when appropriate.

No one cares what language you're speaking at home. It's your right to speak in whatever tongue that you want. It's not your right to make Americans bend over backwards for you so that you can make fools of us by not even trying to assimilate and by turning America into whatever countries that Spanish-speakers came from south of the border.