The Vicksburg Campaign yields a number of lessons for tacticians and strategists. Grant was a talented commander to be sure, but the most important reason for his success was the Union Navy under the able leadership of Admiral Porter. Not just its presence, but the tight coordination between the two allowed one to support the other and vice versa. Land and sea are too intimately connected during amphibious campaigns for the typical supported/supporting relationships to work, there must be symbiosis.