Abolitionists supported the war because it was the most expedient path to end the practice of slavery. That being said, Lincoln didn’t initially set out to abolish slavery. When he was campaigning for president, his goal was to halt the expansion of slavery in the Union, admitting no more slave states; he had no intention of outlawing slavery in existing slave states. In fact, when General Fremont issued an order that would emancipate the slaves of “disloyal” citizens in Missouri (which did not secede), Lincoln immediately countermanded that order. When he pushed for the emancipation proclamation a year later, his intention was not to free slaves, but rather to create chaos behind enemy lines. All slave-holding states that remained in the union were specifically exempted in its language.
And it’s not like he was super anti-slavery in his personal views, either. He didn’t like it, certainly, but he wasn’t above using it to his advantage. When the first black people escaped from slave states after the outset of war, Lincoln decreed that they should be treated as “spoils of war”, and used in the fight against the South. He did not give them a choice in the matter. In essence, though they had escaped to what was supposedly a “free” state, they just ended up exchanging one master for another. To Lincoln’s mind, slavery was a natural consequence of black people and white people sharing the country; his solution was to ship all of the black people in the US over to Liberia.
And it’s not like he was the only person with governmental authority in the Union who had laissez faire attitudes towards slavery. The original proposed 13th amendment, which saw wide bipartisan support in congress, would have prevented Congress from making any laws concerning the abolishment of slavery:
No amendment shall be made to the Constitution which will authorize or give to Congress the power to abolish or interfere, within any State, with the domestic institutions thereof, including that of persons held to labor or service by the laws of said State.
This proposed amendment was sent to the states, but narrowly missed the threshold for ratification.
So yeah; the abolitionists supported the war effort, but to be fair, it was really the only game in town. The union was only anti-slavery as a last resort, as a way to remove the economic incentive for Southern states to secede again.
Edit: just wanted to point out that only some of the abolitionists supported the war. A significant faction of the abolitionists were the quakers, who were vehemently against war.
To Lincoln’s mind, slavery was a natural consequence of black people and white people sharing the country; his solution was to ship all of the black people in the US over to Liberia.
The colonization idea was widely supported at the time, including by prominent free African-Americans. Furthermore, Lincoln’s ideas are greatly shaped not only by the changing conditions of the US, but also by his residency in DC during the presidency, during which he became exposed to more African-Americans than he had before. One of his final speeches was advocating for suffrage for freedmen, for Christ’s sake. The man was racist in a manner not uncommon to his time, but hardly to the degree claimed - that slavery was a natural consequence of a mixed nation.
No amendment shall be made to the Constitution which will authorize or give to Congress the power to abolish or interfere, within any State, with the domestic institutions thereof, including that of persons held to labor or service by the laws of said State.
The Corwin Amendment was a desperate Hail Mary on the eve of the Civil War to try to prevent secession and what the North realized (but the South did not) would be a brutal and bloody war. It failed.
So yeah; the abolitionists supported the war effort, but to be fair, it was really the only game in town. The union was only anti-slavery as a last resort, as a way to remove the economic incentive for Southern states to secede again.
More than that - the Union had become radicalized by the failure of the ‘peaceful’ attempts to contain slavery, by the blatantly traitorous behavior of the South, and by the conditions seen by Union soldiers and government workers in the South, many of whom had not been to slave-holding states before, and certainly most not in a condition where slaves could attest to their own conditions without a watchful eye and ear over them.
The Republican Party itself was quite explicitly an anti-slavery party - the only question was whether it was acceptable to allow it to die out (as Lincoln and the Moderates argued) or if it should be stamped out immediately (as the Radicals argued).
The man was racist in a manner not uncommon to his time, but hardly to the degree claimed - that slavery was a natural consequence of a mixed nation.
I agree with you that his views evolved over time, but your assertion that he did not at one point live up to the degree of racism that I claimed doesn’t mesh very well with this quote from his debate with Stephen Douglas in 1858:
I am not, nor ever have been, in favor of bringing about in any way the social and political equality of the white and black races … I am not nor ever have been in favor of making voters or jurors of Negroes, nor of qualifying them to hold office, nor to intermarry with white people; and I will say in addition to this that there is a physical difference between the white and black races which I believe will forever forbid the two races from living together on terms of social and political equality. And inasmuch as they cannot so live, while they do remain together there must be a position of superior and inferior, and I as much as any other man am in favor of having the superior position assigned to the white race.
At his White House meeting with black thought leaders in 1862, he said:
Your race suffer from living among us, while ours suffer from your presence… It is better for us both, therefore, to be separated
This certainly indicates that he still saw an inequality and animosity between black and white people. And while he did eventually come to agree with those who vehemently opposed resettlement of black people, it was really only after the spectacular failure of Île à Vache (a colony off the coast of Haiti) in 1863-64 that he abandoned his original position.
This certainly indicates that he still saw an inequality and animosity between black and white people.
Which, on its own, is still very far from saying slavery was a natural consequence.