Lumo writes on the subject of my previous post. I fear I left a somewhat intemperate comment. Nonetheless, should the great eraser strike, I repeat it here:
Ah yes, Comrade Stalin, you would fire every researcher who ever studied any question that might be dangerous to your cracked pottery. Your fear of reality suggests that there might be a hint of a scientist hiding somewhere in your fanatical mind, and that the fanatic is terrified that the scientist might wake and send your tower of lies tumbling down.
A couple of points that you might have preferred to ignore: we already have one example of a runaway greenhouse planet in the Solar system: Venus. Also, 5000 ppm CO2 in the atmosphere may or may not have occurred in the past, but if it occurred more than several hundred million years ago, that experience might be irrelevant to today's hotter Sun conditions.
Hardly anybody thinks that the runaway greenhouse is likely for Earth - but one guy who does is the one who first discovered and explained the Venusian one.
The last paragraph is not correct. Hansen played a key role in confirming the Venusian Greenhouse, but Wildt seems to have first proposed it in the 1940's, and Carl Sagan revived in in the 60's.