Why pick on just Mississippi? If you're going to condemn Mississippi, you may as well condemn all the other states who also allow you to marry your cousin:

Alabama
Alaska
California
Colorado
Connecticut
District of Columbia
Florida
Georgia
Hawaii
Maryland
Massachusetts
New Jersey
New Mexico
New York
Rhode Island
South Carolina
Tennessee
Vermont
Virginia

Oh yes, and these states also allow it under certain conditions being met:

Arizona
Illinois
Indiana
Maine
North Carolina
Utah
Wisconsin

If you're gonna tell the truth, tell the whole truth.