Why does lincoln worry about kentucky, missouri, maryland and delaware?

Lincoln was worried about Kentucky, Missouri, Maryland, and Delaware because they were all border states during the civil war. He was worried that they would transform into complete slave states. If they did, the north wouldn’t have much more land and the north would have lost the civil war. He wanted to contain them.

In the midwest because it has more moderate climate than the north or south west which makes farming far easier.