What is it with Americans and Swearing?

What, exactly, do otherwise intelligent Americans find so objectionable about the effective use of swearing? Here’s Seth Godin, marketing guru and otherwise all-round sharp cookie, upholding the grand US tradition of wondering more than seems even remotely reasonable about somebody who likes to put swear words in their books. Who cares? You may as well fret about somebody who puts too much sugar in their tea. File under Impenetrable Cultural Mysteries.