What are the Merits and demerits of totalitarian government?

Merit: If the totalitarian government is benevolent and the people's need are being met the society can achieve spectacular and sublime results, i.e., the Pyramids of Egypt. Imagine, if you would, an ant colony; a total lack of diversity, everyone knows their place and duty, everyone works to the same strictly defined end results and no one person is the wiser.

Demerit: Witness North Korea, Hitler's Germany, etc. The desire for ethnic purity, genetic engineering, thought police, state defined art, bureaucratic corruption, extreme paranoia and ultimately collapse and chaos. Witness the French Revolution.