Your complaint seems to be that Lincoln didn't immediately surrender when Davis started the war. Why would you expect him to?
No. There should have been an cease fire and a negotiated peace agreement. The South had NO DESIRE OR ABILITY to conquer or take over the remaining USA. That concept was laughable then and is now.
When your premise is flawed, there is no reasonable way to answer it. Davis did not start the war. Abraham Lincoln deliberately started the war.
But had Lincoln done nothing, there would have been no war. All he had to do was sit on his hands and leave those other people alone, but he couldn't even do that. He had to meddle, just as Liberals always have to meddle with other people.