What are the main reasons why the united states has a 2 party system today

The two party system was really developed right as our country was founded. There was dispute between two factions of our Founding Fathers over the role the federal government should play in the country. Federalists wanted a strong central government but anti-Federalists were worried about a repeat of the tyranny they faced when they were a British colony so they wanted more power to be given to the states. This split between the Federalists and anti-Federalists eventually led to Democratic and Republican parties we have today.

So that they can check each other to make sure that they aren't being corrupted. But if you ask my opinion they are both corrupt beyond repair.