What legal authority did President Lincoln
From: bragdonb@verizon.net
What legal authority did President Lincoln have to call up 75,000 troops to defend Washington and to order the blockade of most Southern ports?
Modern historians often accuse the South of treason, even though they were exercising what most people at that time viewed as a legitimate constitutional right, the states right of secession. At the same time they ignore actions by President Lincoln. The specific language of Article 3 Section 3 of the Constitution defining treason seems perfectly explicit.
Treason against the United States shall consist only in levying War against them, or in adhering to their enemies, giving them Aid and Comfort.
The Founding Fathers viewed the states as free, sovereign and independent entities.  The Lincoln invasion of the South would seem to clearly fall within the definition of treason as defined in that Article. Lincoln’s actions stood as a bold repudiation of our Founding Fathers and constituted the very essence of despotism as would have been seen through the eyes of Jefferson and Madison. Lincoln’s provocation at Ft. Sumter worked and jumpstarted the nation into a fratricidal war.
On April 15, Lincoln called upon all remaining states to help raise 75,000 militia troops. Lincoln acted upon an obscure 1795 militia law which allowed him to do this but required Congressional approval within 30 days. Lincoln missed that deadline by not calling Congress into emergency session until July 4, 1861, 50 days later. While not unconstitutional, it was a clear violation of the law. Subsequent troop levies for the Army and Navy during this time span were clearly unconstitutional since only Congress could levy troops. The nation was in crisis and Congress was not in session. Due to tremendous opposition in Congress, Lincoln waited until July 4 before he summoned Congress. By July 4, Lincoln had the public support he wanted for war and Congress rubber stamped Lincoln’s prior acts.
Lincoln also had to deal with illegal shipping and smuggling. Wars cost money and the government was run on tariff revenue which basically was collected and paid for by the South. In his 1st Inaugural Address, Lincoln made it perfectly clear that he was willing to use military force to continue collecting the tariffs, knowing that he would be doing this in the ports of another country. A blockade was instituted around the major Southern ports. According to International law, blockades were not recognized without a Declaration of War which Lincoln never sought. 
Lincoln acted ruthlessly with internal dissent caused by his war policies.   Thousands of people were arrested nationwide and placed in confinement without the writ of habeas corpus. Dissident northern newspapers were shut down, their editors often placed under arrest. The case of Ex Parte Merryman decided by Justice Taney ruled that the Lincoln administration violated the constitution by suspending the writ of habeas corpus, something only Congress could do. Lincoln ignored the ruling and even went so far as to have an arrest warrant issued for Justice Taney.
With a series of questionable, illegal and unconstitutional actions, Lincoln aggressively placed the North on a war footing. William Tecumseh Sherman reputedly stated after an initial uninspired meeting with Lincoln that “he was unimpressed and sadly disappointed” and told his brother John Sherman, an important Northern politician, that he “damned the politicians generally,” saying that you have got things in a “hell of a fix”. I don’t think he meant his brother.