It's really hard, because first you have to agree on what the statement means. In the case of your example, what does he mean by "Washington?" Is he talking about the city? Suburbs? Political establishment? Military establishment?
It is, in fact, a straw-man meant to invoke anger and distrust. So your point that the fact-checkers (alone) can't save us is a strong one.
Yes, like most political speeches, it's meant to evoke emotion, but that doesn't make it a straw man. All politicians talk about "Washington" and no, it's not unambiguous, but it doesn't follow that it's a straw man.
It is, in fact, a straw-man meant to invoke anger and distrust. So your point that the fact-checkers (alone) can't save us is a strong one.