Final answer:
President Lincoln's actions during his presidency were debated in terms of their constitutional authority, but they were ultimately supported by Congress and upheld by the courts.
Step-by-step explanation:
President Lincoln's actions during his presidency were often debated in terms of their constitutional authority. Some argued that his use of executive powers, such as the suspension of habeas corpus and the issuance of the Emancipation Proclamation, exceeded his constitutional authority. However, Lincoln justified these actions as necessary measures to preserve the Union and ensure its victory in the Civil War. While his actions may have been controversial, they were ultimately supported by Congress and upheld by the courts.