Clarke may have been reading too much into
Perelandra by interpreting it that way, but Lewis didn't seem to object to that reading in the correspondence, and defended a view that Weston really was an accurate portrayal of what what Lewis saw as a likely future outcome of space-travel, an arrogant war of conquest to dominate the galaxy and subjugate any other worlds that might exist, in pursuit of technology and power.
Among other comments from his letters:
I don't of course think at the moment many scientists are budding Westons: but I do think (hang it all, I live among scientists!) that a point of view not unlike Weston's is on the way ... a race devoted to the increase of its own power by technology with complete indifference to ethics does seem to me a cancer in the Universe.
He also liked to sign off his letters to Clarke with comments like, "I wish you every success except a
practical realization of space travel".
edit: A bit more in the section "Lewis and space exploration" here: http://www.thespacereview.com/article/1754/1
