Why? He wasn't president until 2009.
Because that's when the PRISM program was started. Give credit to who it's due.
Of course, Obama isn't really doing much to make himself look any better, given that he's perfectly fine with it, and even justifies going further. I don't know why he's doing that, but he probably figures he hasn't got anything to lose now that he has gotten himself firmly into his luxurious seat in the White House again.
And as said by others, it's not exactly anything new. The US Government
loves this stuff so much, it's become an addiction.