The political system of USA is a consolidated democracy whereas Brazil and Russia have a mixed system of governance. The US has been a democratic system since its inception, while Brazil has seen military backed authoritarian regimes. Currently is has a democratic federal system, with a President at the helm. Russia was under the communist rule and has been a semi presidential system since 1993. However, Russia now has a system which can be called a soft authoritarianism, with the dominance of one single party.