Actually, the letter is not at all "amazing" to anyone familiar with the real Lincoln. It was a copy of a letter that was sent to the governor of every state urging them all to support the amendment, which had already passed the U.S. Senate and House of Representatives, that would have made southern slavery constitutionally "irrevocable," to use the word that Lincoln used in his first inaugural address. The amendment passed after the lower South had seceded, suggesting that it was passed with almost exclusively Northern votes. Lincoln and the entire North were perfectly willing to enshrine slavery forever in the Constitution. This is one reason why the great Massachusetts libertarian abolitionist Lysander Spooner, author of The Unconstitutionality of Slavery, hated and despised Lincoln and his entire gang.