Those in power seldom have it in their interest to share it. But they also don't want everything to fall apart, either. Perhaps this is the most important reason why those currently in power so openly and casually dismiss any piece of evidence even remotely along these lines. The first order of business: dismiss any and all facts in evidence; to the point of ridicule, if need be - and next, perhaps even more importantly: discredit the messenger. They don't want anyone else to learn the truth - not just yet anyways: not until they have complete control over the situation. And why stop there?