As progressive child labor reformers gained traction during the last quarter of the 19th century, efforts expanded at the state level to outlaw the employment of small children. The move toward state-level reforms proved challenging. Many states, particularly in the South, resisted the effort. Frequently, child labor law opponents denied the problem existed and aggressively extolled the virtues of children in the workplace. This foiled the goal of achieving uniform laws across the country through state action. The failures at the state level caused many reformers by the early 1900s to believe that a federal law might be the best option. The limited role of the federal government under the Constitution, however, made such a prospect difficult. Many constitutional experts, Congressmen, and Presidents believed such a law was unconstitutional. In the face of widespread public support for curtailing child labor, a law based on the Commerce Clause of the Constitution—giving Congress the authority to regulate commerce between states or with foreign nations—was passed in 1916.