 Complete the following phrase:  Porter began naval service as a midshipman at the age of 10 years under his father, Commodore David Porter, on the frigate . For the remainder of his life, he was associated with the sea. Porter served in the Mexican War in the attack on the fort at the City of Vera Cruz. At the outbreak of the Civil War, he was part of a plan to hold Fort Pickens, near Pensacola, Florida, for the Union; its execution disrupted the effort to relieve the garrison at Fort Sumter, leading to Sumters fall. Porter commanded an independent flotilla of mortar boats at the 