Final answer:
The Dred Scott decision accomplished three main things according to Abraham Lincoln. It rendered the Republican Party's platform unconstitutional, exposed the South's Slave Power, and complicated the position of Northern Democrats.
Step-by-step explanation:
Abraham Lincoln identified three things that the Dred Scott decision had accomplished:
It rendered the Republican Party's central platform unconstitutional. The decision declared that Congress could not interfere with the expansion of slavery into the territories, which directly contradicted the Republican goal of preventing slavery's spread.
It exposed the reach of the South's Slave Power. The decision demonstrated that even the Supreme Court seemed to support the Southern perspective, further fueling Northern fears about the increasing influence of Southern slaveholders.
It complicated the position of Northern Democrats, particularly Stephen Douglas. The decision undermined Douglas' strategy of popular sovereignty as a way to placate Southerners while gaining support from Northern voters, leading to further division within the Democratic Party.
Abraham Lincoln identified three major outcomes of the Dred Scott Decision. First, it declared that African Americans could never be citizens of the United States.
Second, it found that Congress had no authority to regulate slavery in the territories, making the Republican Party's platform of stopping slavery's expansion unconstitutional. Lastly, the decision suggested that the institution of slavery was now a protected national institution, removing the distinction between slave and free states.