The guilt by association thing has never made sense to me. I have good, close, long-time friends who are blatantly racist, homophobic, anti-semitic, etc. I just accept that as part of their personality. I know where they stand, they know where I stand, sometimes we'll argue about it, sometimes we'll try to rile each other up over it for fun. At no point have they ever rubbed off on me. If one of my more intolerant liberal friends suggested to me that by knowing these people and not kicking them to the curb for their faults, it must mean that deep down I'm racist, homo-phobic, and anti-semitic, I'd find that laughable and just wrong.
Besides, since most of those friends are also staunch Republicans, does that mean that I'm secretly a conservative too? And how do you reconcile that with the fact that I have so many liberal friends? How can I be all these things subconsciously at the same time?
One of my many favorite qualities of Obama's is his tolerance and easy-going demeanor. It's what allows him to be friends with staunch conservatives who obviously have completely different beliefs than him. It's also what allows him to be friends with people to the radical left of him. I think he understands that people are more than the sum of our flaws. Good people can have repellent beliefs, and knowing them doesn't mean you adopt those beliefs. I'd really hate to live in a world where we could only associate with like-minded people.
At the end of the day, the Hannities and Limbaughs are going crazy over this association stuff because it's all they've got. They scoured everything Obama's ever said or done, and found nothing to suggest he believes these things. So then they went after his friends and associations, and they're trying to use them to prove that the man has somehow completely disguised his true radical self for decades. They're saying we can't believe our lying eyes, and it wreaks of desperation.