Why role does political ideology or politics play in America im regard to political expression?

The two major political parties in the United States, the Democratic and Republican Parties, correspond closely with liberal and conservative ideologies, respectively. These ideologies influence US policy debates, which often concern the appropriate amount of government intervention in the economy or in social behavior.

Although there’s a strong correlation between an individual’s ideology and their party choice, Americans hold a range of opinions on economic and social issues that don’t always fit neatly onto a simple “left-right” continuum. For this reason, some political scientists have proposed a political “spectrum” that charts individual beliefs on multiple dimensions.

(Meaning: conservative ideology - Conservatives tend to believe that government should be small, operating mainly at the state or local level. They favor minimal government interference in the economy and prefer private sector-based solutions to problems. “Social conservatives” believe that government should uphold traditional morality, and therefore should impose restrictions on contraception, abortion, and same-sex marriage. Conservatives are said to fall on the “right-wing” of the axis of political beliefs, a convention that dates from the place where conservatives sat in assembly during the French Revolution.)

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