the problem was not that he used an argument, it was that he made assumptions about why Obama's assumptions might be wrong. It's the equivalent of saying "I don't know shit about this topic, but I don't think you know shit about this topic either based on what I perceive to be our mutual lack of knowledge".
Again, you can't make a deductive argument with something like this. The author is not arguing against making assumptions, you can't avoid it with this topic, simply that the administration's assumptions are weak, short-sighted, and will not accomplish their goal. To say "LOL he used assumptions to attack someone else's assumptions" is a silly and hollow dismissal because, again, this is an inductive debate.