Early DC gun control and the burning of Washington
My Primal Scream has an interesting post on the matter. From 1803 onward, DC forbade its militiamen to show up for muster while carrying arms, and also tightly controlled the possession of flints. By 1812 only a third of its military had the required muskets, and those of course lacked flints. Congress protested without avail.
While there were a great many causes for the American rout at the Battle of Bladensburg (terrible tactics, divided command, use of Revolution War drill in place of the more modern systems evolved out of the Napoleonic Wars), the fact that Washington's militia was largely disarmed and short on flints (and got into position late because it took time to issue the flints) certainly didn't help things.