Stephen Decatur (shown above in a tussle with Barbary pirates) kicked ass pretty handily. Nothing about that changed when he was sent to Algeria in 1815 as Commodore at the head of a ten ship squadron to start up the Second Barbary War. The U.S. was not happy with the way the Algerines had treated her merchantmen during the War of 1812 and Decatur took measures to make sure they understood. He concluded a Treaty of Peace with Algiers on June 30th of 1815.
Without requesting orders from Washington, Decatur sailed his flotilla to the bay of Tunis. He took it upon himself to demand reparations for British prize ships that had been taken from a U.S. privateer by the Tunisians during the War of 1812. Tunis nominally had a treaty with the U.S. at the time which the Dey of Tunis chose to overlook in favor of Britain. When the Dey would not pay up, Decatur's ships trained their guns on the palace and settled in for a siege.
On July 30th, without a shot being fired, the Dey capitulated. He paid Decatur $46,000 in Spanish gold as restitution for the privateer's losses.