As I have used certain words and will always do, what is generally intended by them is to make a light hearted but still meaning full poke or tease at someone in regards to a recent action they had done while diffusing tensions.
When I take a more defiant and often seen as careless and bold some what overbearing attitude about something I would not be one bit offended if someone from a different country and culture called me out as acting like an American.
I am proud to be an American but still my country does not have a spotless and shining record of proper diplomacy or general actions. So by saying stop acting like an American I would get what you are implying from how I may have acted.
If used without proper knowledge and familiarity of the culture and alliterations Every one of these would be dangerously negative and hurtful. However when familiar with the humorous intent behind them they instead showing a point but are intended to still leave everyone with a good humored laugh at what our heritages managed to get associated with at one time or another. So dont take any of these seriously. Someone will think your a lawyer.
Around my area heres what you could expect to hear in public in any place you ever go regardless of the mixed cultures and no one would likely take any offense but rather get a bit of a grin from hearing it instead.
What a German. = Acting proud and stubborn and doesn't listen to reason.
What a Pollock = Acting dumb or stubborn and aparantly doesn't care.
What a Jew = Acting frugal and cheap to the point of it working against them self.
What a Nazi = taking non issues to seriously and imposing your will unjustly in regards to them.
What a Norwegian = Normally intelligent but did something very dumb.
What a Swede = Worked way to hard doing a simple thing.
What a Mexican = Works very hard one day and then avoids work the next.
Must be Irish = Tends to like to argue and fight can also drink heavy with little after effects.
Must be chinese. = Does very cheap, low quality work and a lot of it.
Typical Indian = Refers to expecting large compensation for something that didn't actually happen to them but someone else like them because they are now just lazy.
What Are you, 4? = Having a childish temper tantrum over something stupid.
If used without proper knowledge and familiarity of the culture and alliterations every one of these would be dangerously negative and hurtful. However when familiar with the humorous intent behind them they in stead show a point but still leave everyone with at good humored laugh at what our heritages managed to get associated with at one point in time or another.
Yea I said it twice just so you would be sure to get it!
And I have been called every one of these and far more, and worse as well, too many times to count.
So does any of this make whats often said right or wrong? Well that depends on how old your acting today!