Lincoln’s gamble worked; Lee’s foolish gamble on the third day of the battle did not. Victors write the history books.
Depends on what you mean by "worked". It had *A* result. Not sure I would call it a success. I grew up thinking Lincoln was a great President, and that he deserved a place of Honor in our National history, but as I learned more and more about the events which resulted in the civil war, I began to have less and less respect for the man.
Lincoln was the first to create and use the power of the almighty state, and the nation has never been the same. Yes, he accomplished a great good as a result of using this power, but he established the precedent for a lot more subsequent abuse of this power.
Woodrow Wilson merely built on Lincoln's established principles.
What you say comes down to the last line of my post: Victors write the history books. It could be argued that if Lee had not fought the third day at Gettysburg, the South would have had time to finish implementing the changes they were working on. 300,000 Black soldiers, trained and fighting for the promise of land and equality would have changed things. Once the war began, whether Slavery was the prime mover or not, Slavery was finished. With the historical result, we moved considerably toward Federalism.