one major difference
Critical thinkers exist everywhere, but one major difference (as stated earlier) between Europe and the US is that in Europe mistrusting your Government is a basic principle. Most people will tell you not to believe everything you read in the newspaper, but they are even more sure that Government officials are not necessarily having their constituents' interest at the top of their agenda.
In the US it seems to be the opposite: bashing media for being biased or having a certain agenda is the accepted notion, whereas it is considered un-American or unpatriotic to question the motives of the President or other elected officials...