I suppose it comes from thinking in paradigms rather than looking critically at reality. So if your mental paradigm is that colonialism was and is morally wrong, and that historical colonialism has been replaced by 'cultural colonialism', your perception of the actions of the Allies fits into the 'colonial aggressor' slot in that paradigm, then the actions of the 'colonial aggressor' and anyone who shares their agenda is ipso facto 'repressive of human rights' and therefore anyone who opposes them, is 'supportive of human rights' regardless of what they actually do to oppose them. Remember 'consciousness raising' at university? The nice thing about arguments that start with the premise that 'what you think is happening isn't what's really happening, because your consciousness is impaired from living in this twisted society' is that you can get to such interesting and provocative positions without worrying about such inconveniences as the facts.