What ended the era of dual federalism?

However, the departure from this view became evident with the ratification of the Sixteenth Amendment to the United States Constitution (income tax) as well as the Seventeenth Amendment to the United States Constitution (direct election of federal Senators).

-Wikipedia

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http://en.wikipedia.org/wiki/Dual_federalism#Departure_from_this_view

The era of dual federalism began to fade away in the early 20th century and was ultimately brought to an end by a series of historical developments and influential Supreme Court cases. Dual federalism is a concept in which the powers and responsibilities of the federal and state governments are clearly separated, with each entity having distinct authority over different policy areas.

1. Commerce Clause: One of the main factors that contributed to the demise of dual federalism was the reinvigoration of the Commerce Clause of the United States Constitution. The interpretation of this clause evolved over time, granting the federal government more authority to regulate interstate commerce. This expansion of federal power was reinforced by the landmark Supreme Court case of Gibbons v. Ogden in 1824, which affirmed the federal government's ability to regulate any commerce that crosses state lines.

2. The Civil War: The Civil War, fought from 1861 to 1865, also played a significant role in shifting the balance of power between the federal and state governments. As a result of the Union victory, the federal government's authority was reinforced, and the primacy of the federal government over state governments was solidified.

3. Progressive Era: The Progressive Era, which spanned from the late 19th century to the early 20th century, brought about a wave of reforms at both the state and federal levels. This period saw the rise of political movements advocating for stronger federal regulations on issues such as labor conditions, food safety, and child labor. Progressive policies and the desire for national uniformity in implementing them led to an expansion of federal power and the erosion of the dual federalism model.

4. New Deal: The most decisive blow to dual federalism came during the Great Depression of the 1930s, when President Franklin D. Roosevelt introduced his New Deal programs. These programs aimed to combat the economic crisis and included a range of federal initiatives aimed at stimulating the economy, regulating the financial sector, and providing relief to the unemployed. To implement the New Deal, the federal government had to assume powers that were traditionally within the domain of the states. The Supreme Court, in a series of rulings, expanded the interpretation of the Commerce Clause and upheld many of the New Deal programs, further solidifying the federal government's authority.

In summary, the era of dual federalism gradually came to an end due to evolving interpretations of the Commerce Clause, the influence of the Civil War, the progressive reforms of the late 19th and early 20th centuries, and the expansion of federal power during the Great Depression and the New Deal. These historical developments shifted the balance of power from the states to the federal government and set the stage for the modern era of cooperative federalism.