There are many reasons why third parties do not last , two of the main are lack of money and Lack of popularity . Another good reason would be they don't have the same interest that most citizens would want.
c it’s the correct anwser explanation never did this
Constantine allowed Christianity to become a religion. Other emperors made Christianity the main religion
There wouldn't be a USA, and...
the Indians would still have pretty much all of the Middle-west of the USA.
Hawaii would still be under their kings/queens
Alaska would still be part of russia
China would pretty much never had any technological progress (they isolated themselves)
Japan would still be going around with pretty much katanas.
etc etc
if you want more i can give you more (if you want information on why one is on the list, post it in the comments)
hope this helps
