ATS linked up this new economist article with some very interesting, and relatively even-handed, observations on how, and why, the United States is unique:

In terms of income per head, America is the wealthiest large industrial country. It is also the only western democracy to have practised slavery in the industrial era. It has the highest crime rate and highest rate of imprisonment (though crime, at least, is falling towards European levels). Its society is among the most religious in the world. Perhaps less obviously, Americans are more likely than almost anyone else to join voluntary associations.

Very interesting read.