The only answer to this question must be that pool of available right-wing, racist pseudo-scholars is very, very small.
Reading this - even the headline - was an exercise in discipline for me.
I suppose I could spend a whole lot of time showing that Murray either doesn't know that history might make all the difference in the world between European countries and the United States, or doesn't believe it is true. After all, this is a guy who wrote an entire book on the importance of IQ, which no serious researcher in neuroscience considers worthy of a second glance (and even his book, The Bell Curve, was deeply flawed research on any number of levels), so it might just be that he blithely types away, thinking he's saying something important when in reality he is just being really stupid.
I could do all that, or I could just say . . . Bwahahahahahahahaha!