The government, regardless of systems of power and administration, always run a big part of a country. The most democratically elected leaders have conducted the most heinous crimes on humanity (Hitler, Bush 2). While the most absolute dictators have conducted the most peaceful, beneficial deeds (Brunei, which is also Islamic). It depends on the leaders, culture and the time. Economically, the most powerful capitalist systems have yielded the most horrific depressions and destruction of wealth (USA). While the most benign socialist implementations have created a most happy sustainable people (Scandinavia). 

History's most self-righteous people, who ceaselessly lecture the world on Christian morality, human rights and democracy, is also the same people who warred ceaselessly for 1500 years in Europe. Who grew its empire of great power using African human slave trade that killed millions, destroyed that continent. Then started 2 world wars killing some 75 millions. In splendid monarchy.