Abraham Lincoln is widely considered to be one of the country's greatest presidents, and indeed, he possessed some significant strengths that helped him lead the North through the Civil War. First, Lincoln was an excellent speaker who could communicate well with friends and foes alike. He could clearly and concisely express his goals, encourage the nation in times of difficulty, and inspire morale through speeches like the Gettysburg Address and his second inaugural speech.
Further, Lincoln was a highly intelligent man who could balance numerous perspectives and find middle ground between radicals and moderates. He was open to being taught, quick to learn, accepting of disagreement, and able to share both credit for the nation's successes and blame for its failures.
Lincoln did, however, have his weaknesses as a wartime leader. First, he had no military experience whatsoever. This made it difficult for Lincoln to serve in his capacity as commander in chief, choosing generals, planning campaigns, and making necessary changes. He left General George B. McClellan in place long after he had already shown his inability to properly lead the Union army, for example. He also hesitated over strategy, allowing himself to be influenced even when he questioned his generals' ideas.
Lincoln was also quite careless about the civil rights of citizens. He suspended the writ of habeas corpus, for instance, allowing Northern officials to arrest and detain civilians without charge or trial. His orders of conscription were also constitutionally questionable. Lincoln often set aside the law and the Constitution when such served his purpose, bending the rules in favor of his own agenda.