Sorry about the brevity of my last post. I think there are fundamental differences between the two parties. This won't be an all inclusive post but I hope it will give you a bit more clarity on the rifts (some vast, some not as much) on the differences between the two parties.
Overall Role of Federal Govt:
Democrats: generally believe it is the government's role to regulate the free market. Without regulation greed and poverty rule the day.
Republicans: generally believe government regulation hinders the free market. Regulation prohibits market growth which in turn prohibits growth for everyone.
I am painting with a broad brush here but I think fundamentally that is one of the biggest core differences between the Left and the Right in this country and I think it dictates the stances on many individual policy issues.
TAXES:
Left: as income increases, taxation increases on a percentage basis.
Right: taxation should be the same percentage for everyone.
HEALTH CARE:
Left: universal health care for all. Programs like Medicare and Medicaid for the elderly, disabled, and poor.
Right: the private sector is a better because the govt wouldn't be able to effectively run health care.
IMMIGRATION:
Left: generally support making immigration easier.
Right: generally believe in strict immigration.
Both do believe it should be regulated.
ENVIRONMENT
Left: strong belief in protecting the environment. Beyond retaining natural beauty the belief is that protection is necessary to avoid destroying the environment.
Right: government protections hinder the country's ability to use it's natural resources. This creates reliance on others and prohibits growth.
RELIGION
Left: generally believe religious beliefs should not play a role in policy. The nation was founded on religious freedom and policies shouldn't infringe on other people's religious beliefs.
Right: generally favor Christian beliefs playing a role in govt policy.
DEATH PENALTY
Left: generally favor life sentence vs death penalty.
Right: generally favor death penalty.
Definitely not as clear on this one. Both sides have a lot of crossover.
GUN CONTROL:
Left: favors varying levels of gun control.
Right: favors less gun control.
Both believe in the 2nd Amendment...just disagree about it's application.
ABORTION:
Left: generally believe it's the woman's right to choose.
Right: generally believe abortion should only be legal in extreme cases.
This is getting way into TL;DR length. This is not all inclusive just a few of the issues off the top of my head.
