Why is it difficult for third parties to win elections in the united states

What happened to segregation laws after the case of plessy v. ferguson? segregation still existed, but only in very small towns with no access to court systems. important politicians like ferguson, once in favor of segregation, began to denounce it. plessy v. ferguson began the breakdown of segregation as it was defined at that time. segregation continued, and citizens experienced many more years of legal segregation.

Brainles asap!me : -how has religious fundamentalism been used by extremists in the middle east?

The articles of confederation did not allow the government the power to tax or to force the states to do anything. what challenges could this cause