The filmmaker interview for tonight’s “Elsewhere Live” is with Why We Fight director Eugene Jarecki, and even if I do say so myself I think it’s the best discussion I’ve ever done since the program began. I kept my questions simple and kept my irritating “uhm-hmm” sounds to a minimum and just let the guest go to town. And Jarecki is brilliant, and so is his film, which I’ve just seen for a second time. Why We Fight will have its New York and L.A. debut on 1.20 and then spread out from there.