McQueen was elected as a Democrat to the 30th and
31st Congresses to fill the vacancies caused by the death of Alexander D. Sims. He was reelected to the 32nd and to the four succeeding Congresses, and served from February 12, 1849, until his retirement on December 21, 1860.
American Civil War
An ardent supporter of slavery and southern states' rights, McQueen was elected as a representative from South Carolina in the First Confederate Congress after the outbreak of the American Civil War. Regarding the Confederacy's cause for starting the war, McQueen stated in a December 1860 letter to civic leaders in Richmond, Virginia:
I have never doubted what Virginia would do when the alternatives present themselves to her intelligent and gallant people, to choose between an association with her sisters and the dominion of a people, who have chosen their leader upon the single idea that the African is equal to the Anglo-Saxon, and with the purpose of placing our slaves on equality with ourselves and our friends of every condition! and if we of South Carolina have aided in your deliverance from tyranny and degradation, as you suppose, it will only the more assure us that we have performed our duty to ourselves and our sisters in taking the first decided step to preserve an inheritance left us by an ancestry whose spirit would forbid its being tarnished by assassins. We, of South Carolina, hope soon to greet you in a Southern Confederacy, where white men shall rule our destinies, and from which we may transmit to our posterity the rights, privileges and honor left us by our ancestors.[1][2]