The Northern people were tired of the war, they were tired of piling up a debt which would be a further mortgage upon their homes.
Mr.Lincoln, I believe, wanted Mr.Davis to escape, because he did not wish to deal with the matter of his punishment.

He knew there would be people clamoring for the punishment of the ex-Confederate president, for high treason.

He thought blood enough had already been spilled to atone for our wickedness as a nation.

At all events he did not wish to be the judge to decide whether more should be shed or not.

But his own life was sacrificed at the hands of an assassin before the ex-president of the Confederacy was a prisoner in the hands of the government which he had lent all his talent and all his energies to destroy.
All things are said to be wisely directed, and for the best interest of all concerned.