[BroJoeK]

from Dwyer's article: "On May 3, he called up thousands more troops — for three-year hitches — another act the law did not authorize the president to commit."

Lincoln's action, while Congress was not in session, called for volunteers.
Nobody was forced to enlist.
Lincoln specifically recognized this in declaring:

"The call for volunteers hereby made and the direction for the increase of the Regular Army and for the enlistment of seamen hereby given, together with the plan of organization adopted for the volunteer and for the regular forces hereby authorized, will be submitted to Congress as soon as assembled.

"In the meantime I earnestly invoke the cooperation of all good citizens in the measures hereby adopted for the effectual suppression of unlawful violence, for the impartial enforcement of constitutional laws, and for the speediest possible restoration of peace and order, and with these of happiness and prosperity, throughout our country."

When Congress returned, it supported everything Lincoln had done.

[donmeaker]

By contrast, Jeff Davis had previously called up 100,000 men to support the insurrection, demanding that soldiers serving as militia be provided.

In violation of article 3 requirement that controversies between states and the federal government be resolved at the Supreme Court.