Feb 6 1812: Volunteer Bill
In 1812 there was as of yet no legal way to declare war in the US and for that matter no way to make militia-men invade another country.
On February 6, 1812, President James Madison signs the Volunteer Bill into law. The bill had passed the House of Representatives on January 17, 1812 by a vote of 87 to 23. The law authorized the President to accept up to fifty thousand volunteers from the states. The President could only call on the volunteers for three purposes: to execute the laws, to put down an insurrection and to repel an invasion.
An amendment making volunteers able to leave the US to invade another country had been shot down. Not quite what Madison had wanted but he was part of the way there. He now had his army, too bad he couldn’t use them … yet