In that you are correct in my opinion. Lincoln would probably not have taken any action to end slavery in the United States. His opinion was that based on the Supreme Court ruling in Scott v. Sanford, he had no constitutional authority to use the Federal Government to interfere with slavery where it was legal. This, however was not the view of some of the Southern States which chose to withdraw from the Union. Their belief was that a Republican controlled House and Senate in unison with a Republican President would, at some point in time, take action to end slavery as it existed in 1860. The only avenue left, in their view, was to withdraw beyond the power of the Federal Government. Hence, secession was the answer to allay their fears.