Censorship is generally not a wise response to a single instance of any problem. Every increment of censorship you impose will wipe out an unexpectedly broad swath of discussion, make it easier to add more censorship later, and make it harder to resist accusations that you implicitly support any post you don't censor.

If you feel you have to Do Something, a more narrowly-tailored rule that still gets the job done would be something like: "Posts that directly advocate violating the laws of <jurisdiction in which Less Wrong staff live> in a manner likely to create criminal liability will be deleted."

Because, you know, it's just about impossible to talk about specific wars, terrorism, criminal law or even many forms of political activism without advocating real violence against identifiable groups of people.