Bob Zubrin and I rhetorically duke it out over at Pajamas Media. This exchange actually occurred several weeks ago, but it was only published this weekend.
[Update a while later]
Unfortunately, since I went first, Bob got the last word, but that’s why I have a blog. I’ll note that I find it utterly bizarre that he sees no value in orbital propellant storage (today was the first time I’ve seen his final response). Does he really think that all missions to Mars will originate from the surface of the earth, forever more? I’ll note also that he vigorously kicks the stuffing out of a strawman with talk of the problems of the orbital mechanics. It sort of reminds me of the arguments that missile defense proopponents used to make in places like Scientific American, coming up with some ridiculous way of accomplishing the thing, pointing out how ridiculous it was, and implying that there are no sensible alternatives. He doesn’t even mention Lagrange points, which obviate most of the plane-change issues.
One other thing. I think that his ad hominem attack on Jeff Greason was both gratuitous and laughable. Does he really believe that a) no one else on the Augustine panel favored propellant depots and b) that the only reason Jeff supports them is because they provide a market for a vehicle that he might build some day? Really?
[Update a couple minutes later]
In rereading his final rebuttal, I notice that he didn’t respond to much of what I had to say, particularly with regard to ending Apollo and the difficulty of doing what he wants to do, and making long-term space plans in a representative republic — he just repeated the same things he always writes.