Pardon my ignorance, but why is it that Deep Blue can't be recreated on a reasonably fast modern PC in software? In fact, why is it that this sort of program wo

Pardon my ignorance, but why is it that Deep Blue can't be recreated on a reasonably fast modern PC in software? In fact, why is it that this sort of program would be considered difficult at all? EDIT: answered my own question via wikipedia "In a recent match, Deep Fritz vs. Vladimir Kramnik in November 2006, the program ran on a personal computer containing two Intel Core 2 Duo CPUs, capable of evaluating only 8 million positions per second, but searching to an average depth of 17 to 18 plies in the middlegame."