I Drive a German/Japan made car. No Issue
The word "Luftwaffe" in its meaning may mean AIR Force that I don't have any issue with But Many people will - as has been posted in some of the other posts tie the word to Nazi Germany.
-and having some one put USAF will not get the same reaction because in WWII
the US stood for justice and were not fighting to take over the world. and eliminate Jews off the face of the planet.
Do whatever you want its your car BUT I would strongly suggest going against "Luftwaffe" on your plate.
Not cool in my book......
this is only my opinion...so good luck with whatever you decide