was he involved in any war?
Yes, the War of 1812
John C. Calhoun
War of 1812 
who had a cousin who was a strong supporter for independence John C. Calhoun who is he? An American statesman and political theorist what was his role in the politics? He began his political career as a nationalist, modernizer, and proponent of a strong national government and protective tariffs.
wiki:5363761
John C. Calhoun [SEP] Introduction
He saw Northern acceptance of those policies as a condition of the South remaining in the Union. His beliefs and warnings heavily influenced the South's secession from the Union in 1860–1861. Calhoun began his political career with election to the House of Representatives in 1810. As a prominent leader of the war hawk faction, Calhoun strongly supported the War of 1812 to defend American honor against British infractions of American independence and neutrality during the Napoleonic Wars. He served as Secretary of War under President James Monroe and, in that position, reorganized and modernized the War Department. Calhoun was a candidate for the presidency in the 1824 election.