Some time in the late 80's right before he died. It was a small part of a longer interview with a mag (so not on camera just text)... Due to it being in the 80s its obscure on the net so ill need some time to hunt it down again but to paraphrase he said star trek ships where exploration ships and in a smallersociety where star wars ships are meant for war in a much larger society with more ability to mass produce war ships. In short he admits that the title of the two series matter if the two societies ever duked it out, an exploration adventure story would be conquered by the industrial war story. Don't forget though most trekies ignore this kinda thinking and just argue that Q can do anything (though now its been showen in TCW the Whills can pretty much create or destroy life at will too by simply touching it)... Or argue time travel (though being too dumb to realize their ships are too slow to get to a GFFA and whipe them out in the past). Also remember Gene hated Wrath of Khan even more than Lucas hated Empire, Gene's vision of Star Trek is only really represented by the first two season of the original series and first 2 of TNG... He produced only a fraction of all the Star Trek material unlike George Lucas who even now still has vast influence even after he sold the rights. in other words Gene's vision of Trek isnt what most fansview it as even more so than OT fans disagreeing with the PT.