I would agree with the notion that American's are motivated by varying degrees of greed.  I do however, wonder why some demographics (read race if you must) put material to the exclusion of their fellow man.  Our prisons are filled with people from a certain demographic.  I do sincerely believe that their race is a coincidence.  I think the reason is the spike in young parents under 19 during the mid to late 80's.  A lack of wisdom would undoubtedly be passed down to the next generation.  The whole "Forget you, I got to get mine's" mentality that I witness in this age group points me in this direction.  This, is, also, of course, the MTV hip hop generation.  So I think the racial divide is not really a racial divide, just a lack of good parenting/supervision during a certain time period.  The people born during this period are now old enough to show us what they've learned.    Heres a link to some statistics compiled by the Guttmacher Institute: http://www.guttmacher.org/pubs/2006/09/12/USTPstats.pdf