Because Bush has had nothing but success in his foreign policy:

President George W. Bush on Thursday sharply criticized Democratic front-runner Barack Obama’s pledge to meet Cuban leader Raul Castro without preconditions, leaping squarely into the race to succeed him.

“I’m not suggesting there’s never a time to talk, but I’m suggesting now is not the time … to talk with Raul Castro,” Bush told a White House news conference.

So Bush doesn’t approve? Sounds like a great plan Obama has then. Why would anyone take suggestions from the biggest failure in the history of U.S. Presidents?