Slavery was a state issue when the GOP was founded.
Ansel, the issues I brought up are clearly not powers the Federal Government possesses: marriage and medicine are not part of the Federal powers. Those are powers left for the states.
There have been many instances of Congress passing laws that are clearly not Constitutional - like ACA and DOMA.
As for slavery, it is a crime against God, and the Declaration of Independence clearly stated that all men are created equal; an inalienable right. The fact that some states had businessmen who made money trafficking in human bondage and misery, and based it all on unconstitutional state laws is not my concern.
You should know better.