Quite a few things in here that needs an explanation.
America loves to meddle in other countries affairs, despite knowing very little about the countries.
Doing World War 2 the Swedes let Germany walk through Sweden, which allowed them to invade Norway.
That pissed Norway off quite a bit, and for many years after that it was custom for Danes, if they were having a party where both a Swede and a Norwegian would show up, to never place them at the same table or anywhere near each other, because otherwise they were sure to start fighting.
Poland is wearing a burglar’s bask because if anything is stolen in Scandinavia, it will most likely turn up in Poland. Not necessarily because it was a Pole who stole the thing in the first place, but because that’s where a lot of people go to get rid of their stolen goods.