That's the way they put it over at Think Progress. I've watched the video. Rand Paul asks a question. It seems histrionic to equate asking a question with pushing a conspiracy theory, and the truth is Hillary Clinton's answer has the ring of... lying.
The effort on the left to stereotype Rand Paul as a nutcase is so strenuous that it stimulates my root-for-the-underdog instinct. And makes me suspicious. I feel a Rand-Paul-must-be-destroyed conspiracy theory blossoming within.