Why did the united states support south vietnam rather than north vietnam after the french left?

The United States wanted to prevent communism from spreading.

he was sent to prison on various charges for protesting south africa's policies of apartheid

could you use this to with a topic?

the key difference between a democracy and a republic lies in the limits placed on government by the law, which has implications for minority rights. both forms of government tend to use a representational system — i.e., citizens vote to elect politicians to represent their interests and form the government.