[jerf]

No, it's much weaker than that... that assumes that our understanding of relativity is even remotely correct. You can obtain the FTL/causality problem from even a brutally simplified version of general relativity, such that one can literally draw the problem on a piece of paper. For FTL not to break causality essentially requires that A: you can only FTL jump once and only once in the entire history of the universe as long as you don't leap into your own past light cone, B: FTL is impossible or C: Causality is not absolute.

I've often thought that the announcement that we've developed FTL would actually be a very bad thing, as fun as it sounds at first. Sort of like this story, where it turns out a proof of P = NP is just about the worst possible thing: http://www.antipope.org/charlie/blog-static/fiction/toast/to...