In his “House Divided” speech Lincoln expressed the expectation that one way or the other constitutional slavery would end.
Everyone, North and South, knew Lincoln would not likely have the votes to end constitutional slavery peacefully in his lifetime using the amendment process.
However, if he could parlay 39 percent of the popular vote into a presidency; if he could gain control of the military he could levy war against the states and violently overthrow constitutional slavery. And the Constitution.
First he would need a pretext for war. This he found using the navy in the Gulf of Tonkin Incident.
I meant to say, the Fort Sumter Incident.
Fort Sumter was a "pretext" only in the same sense that, for examples, Pearl Harbor and 9/11 were "pretexts".
All had the effects of convincing all Americans that war had begun in earnest.
"Mr. President, at this time it is suicide, murder, and will lose us every friend at the North.
You will wantonly strike a hornet's nest which extends from mountain to ocean, and legions now quiet will swarm out and sting us to death.
It is unnecessary; it puts us in the wrong; it is fatal."[19]"