Sports and politics shouldn't be mixed up but, unfortunately, they are; everything is nowadays some way or another connected with politics. And I whole-heartedly agree: it is no use if a handful of countries decide to boycott the Olympics. They all should boycott the games if they really want to make a difference or take a stance. On the other hand, some athletes have used tha last couple of years practising especially for this event. It would be quite unfair to them if they weren't allowed to participate. Quite a byzantine issue, I daresay.
Oh, and, on top of this, there have been rumours that some athletes might boycott the Olympics because some animals are treated like dirt in China and in Asia overall. Take bears, for example. It's quite abominable what they do to bears in order to get bear bile. The method they use to get the bile is atrocious, to put it mildly. The bile is supposed to be a panacea or something.