I can provide the answers to your questions:
1. The controversial political doctrine you are referring to is known as "Popular Sovereignty." It allowed residents of a territory to decide through popular vote whether to legalize or prohibit slavery before joining the Union. An example of this was the Kansas-Nebraska Act of 1854, where the issue of slavery was determined by the residents of the territories rather than Congress.
2. The act in 1862 that authorized Lincoln to enlist black men as soldiers was the Emancipation Proclamation. Although it did not specifically enlist black soldiers, it paved the way for the recruitment of African American troops into the Union Army, significantly impacting the course of the Civil War.
3. The act in 1861 that stated that any slaves used by their masters to benefit the Confederate war effort would be freed was the Confiscation Act of 1861. This act allowed the Union to confiscate property, including slaves, used in support of the rebellion, leading to the liberation of those enslaved individuals.
