A breakdown of deaths caused by secular left-wing and communist governments for your consideration:
20 million in the Soviet Union
65 million in the People’s Republic of China
1 million in Vietnam
2 million in North Korea
2 million in Cambodia
1 million in the Communist states of Eastern Europe
150,000 in Latin America
1.7 million in Africa
1.5 million in Afghanistan
10,000 deaths “resulting from actions of the international communist movement and communist parties not in power.”(p. 4)
He did leave out Cuba, though, and the Mexican socialists.