Interesting factoid from the History Channel (I know, I know it's only a TV show): It seems that the Purple Hearts being given out today are left over from WW II. During the planning for the invasion for Japan about 400 thousand Purple Hearts were ordered and fortunately they weren't needed so the Purple Hearts given out still today are left over from that order.
. I've read somewhere ( Time magazine ? ) that there was a massive stock of battleship shells left over from WW2 even after the 35.000 t class got decommissioned , when the Missouri got refurbished there was some hope of finally using them , hope now gone .