But law does not dictate a right. Our founding fathers believed that rights are bestowed by God, regardless of the law of the land or anything else, and that a good government protects those rights.
And that is, in fact, the consensus of the world...that rights exist regardless of what the law dictates, and laws that violate those rights are in fact laws that oppress and violate humanity.
The law making it legal to abort is one of those laws, along with laws that dictated the legality of slavery, and laws that allow tyrants to butcher and murder their people, or laws that allow the strong to kill and subjugate the weak. Those are bad laws, and regardless of the fact that they are laws does not change the fact that the people they are enacted against have a right to be protected from them. Even if it means going against the law that dictates the legality of the oppression.