U.S. Stock Premium

Was watching Bloomberg TV the other day, a segment mentioned the forward P.E. ratios of the Hang Seng Index and the Eurostoxx 50.  They were between 8 and 9.  The S&P's is 12.7.  That is a 40-50% premium for U.S. stocks over Hong Kong or European stocks based purely on forward P.E. ratios.  That premium seems grossly out of line with historical norms.  For those saying that U.S. stocks are cheap, then overseas stocks are cheaper than cheap.