Section #1 - The Life of Abraham Lincoln
Chapter 60: Lincoln Plans His Strategy With Legal Issues in Mind

As a student of the Constitution, the President is careful about how he intends to position the conflict and then use his special powers as Commander-in-Chief to accomplish victory.
He begins by refusing to label the Confederate cause a War and instead calls it an Insurrection. That’s because he says a War by definition is between two independent nations, and he has no intention of acknowledging the rebel government that way. In turn, his wish it that Britain, France and other global powers will agree, and refuse to officially recognize the Confederates or supply them with much needed armaments.
Calling it an Insurrection also fits his battle cry of “Save the Union” – a call he hopes will motivate the sacrifices needed from both the public and his soldiers.
Beyond that, Lincoln is also drawn to testing the potential powers he has as Commander-in Chief to “defend the Constitution of the United States against all enemies, foreign and domestic.”
Throughout his tenure in office, the President will assert that his duty to protect the nation allows him to take actions that either violate the Constitution, like suspending habeas corpus, or stretch the power of the Executive Branch, as in the Emancipation Proclamation.
He will later employ this same argument to ensure the official end of slavery.