I will remember this post when a great Rabbi passes and is posted in the RIP thread. Everyone will have you to thank for my negative posts then.
That works if the great rabbi you're referring to was also a politician, and that's why everyone is posting about him or interested in his death - otherwise, it's mourning his death just like every other great rabbi's death. In the same way, if McCain's death would be mourned in the same way as every other heroic POW, it would have nothing to do with politics.
note that I'm not discussing write or wrong here, just pointing out that your logic does not follow.