Answer:
The nullification theory is based on what the 10th amendment of the U.S. Constitution didn't say. The 10th amendment granted states and the people reserved rights that wasn't granted to the Federal Government in the Constitution. Since 1796 when Thomas Jefferson and Thomas Madison first tried to nullify tariffs felt unfair to the South, there were many attempts to pass an "Ordinance of Nullification" including then Vice President John C. Calhoun to over turn the tariff acts of 1828 and 1832, that began the succession movement in North Carolina, to allowing the southern states to establish a "separate but equal clause" for minorities.
If one is for the nullification acts, they prefer a weaker national government and a stronger cause for states rights. The reverse is true if your against nullification acts.
In many commerce cases today, the 10th amendment is repeatedly tested.