I have read the Lincoln-Douglass debates. Lincoln, if he had his way, would have outlawed slavery by executive order. But under the Constitution, he had no such power and never once claimed such authority. His only objective when elected was to resist further expansion of slavery into the territories.
After secession, he did on many occasions plead to the four Union slave states to enact legislation that would end slavery in their states -- two did and two didn't.
He offered to support compensation from the federal treasury for slave owners in a gradual emancipation scheme. He made very clear that he viewed slavery as a sin on the nation.
I, if President and had my way, would with a stroke of a pen outlaw Abortion of Demand which I view as a sin on the nation.
But under the Constitution, that is not possible. Like abortion today, slavery was a 'legal' institution.
To ban either would require a Constitutional Amendment or in the case of abortion on demand, the overturn of Roe v Wade and for the States to individually outlaw the practice. Today, some states would ban abortion ( as some banned slavery before the Civil War) -- but most wouldn't.
What Lincoln did with the EP via his war-time powers as CiC was to move the focus the war to the only real issue that caused the divide between the states to begin with -- that is slavery. It made slavery the issue and caused Americans not touched so much by slavery to become aware of the cancerous effect it had upon the nation.
Today, if we could make more Americans aware of the cancerous effect of abortion on demand, I think we could gain enough support of a Constitutional ban.
The EP was a large gamble on Lincoln's part, but in the end, it worked. We ended with a Union and the totally un-American institution of slavery was ended. Without the EP, it 'could' have ended with a Union (likely not), but with the institution of slavery still very much intact which would have only set the stage for the next war. P>