have yourself a merry little christmas party joke

Tis the season to be jolly, and tell lots of jokes and laugh at them. So here is a little gem I heard at one of my christmas parties this year. 

A rabbi is sitting on an airplane next to a Korean guy.
 After they have been flying together in silence for a
 while, the rabbi leans over and says, "You know, I've
 never forgiven you Chinese for what you did at Pearl
 Harbor."
 The Korean looks shocked and replies, "What the hell
 are you talking about?!?!?  It was the Japanese that
 bombed Pearl Harbor, not the Chinese.  And besides,
 I'm not Chinese or Japanese, I'm Korean!"
 The rabbi says, " Korean, Japanese, Chinese, what's
 the  difference?"
 A little while later, The Korean man says, "You know,
 I've never forgiven you Jews for sinking the Titanic."
 The rabbi looks confused and mad and says, "What are
 you talking about?  The Jews didn't have anything to
 do with that!  An iceberg sank the Titanic.
 The Korean guy replies, "Iceberg, Goldberg, Greenberg,
 what's the difference?"