The reason is because of who his advisors are.
Noah Pollack asks the legitimate question:
Does anyone think that if the time comes that Power has President Obama’s ear, she will advise him to do anything other than repudiate America’s greatest ally in the Middle East in favor of appeasing its greatest enemy? And here’s an even better question: Does Barack Obama have a single adviser who would tell him to do anything else?Let's add this to that delegation to Syria led by Obama advisor Zbigniew Brzezinski, who was most famous as Jimmy Carter's national security advisor when the Soviets invaded Afghanistan and the Iranians stormed our embassy (arguably the first overt signs of the danger we now face). Relying on Jimmy Carter's advisors should be a prima facie downcheck on national security.
This is not about Barack Obama's patriotism. As far as I know, he at least talks a good game, although methinks he doth protest too much. I certainly think it is fair to request that he explain why he accepted a contribution from a former member of Weather Underground, and that he be asked if he agreed with the comments of that supporter that were printed in the New York Times on 9/11.
He can complain about people raising this point, and can say he condemns their actions all he wants, but the fact remains that he took the money notwithstanding his objections to the Weather Underground's actions. So it seems that those actions of the Weather Underground bothered him, but not so much that he couldn't accept contributions from them. It's a lot like Michelle Malkin and some of the unacceptable rhetoric on immigration she looks the other way on.
I didn't give Malkin a pass on her questionable associations on immigration, and she's just a columnist. So why should I give Barack Obama a pass on his questionable associates when he wasn't to live at 1600 Pennsylvania Avenue, NW in Washington, DC?