Hire the best you can find

Lincoln possessed the ability to look past his own ego to the underlying talent, ambition, and morality of a person. Although it wasn’t at all necessary, he appointed a cabinet made up of people who had slighted him, competed against him, resented him. He did this only because he knew that they were the best people for the job and he wasn’t interested in people who would cater to his ego, he was interested in people who could save the Union, so he chose the best he knew of, despite what they “did to him” in the past, despite the fact that they all felt the wrong man had been nominated.