The dad wasn't even around when Obama grew up. There was nothing concrete against Obama Senior in that article, just general suspicions against the group as a whole. And conservatives should make it a point to judge individuals on their own actions- not their dad's.
Nature *and* nurture....genetics *and* upbringing.
“Like Father, Like Son” is not just a goofy aphorism. Genetics obviously plays a significant role in determining who you are. Take a look at most communists in the west and you’ll find dear old Mum or Dad were commies, too. It isn’t all explained by “nurture.”