Exploring Federalism in the U.S. Constitution and Contemporary Issues

In the context of the American governmental system, the principle of federalism operates as a core element influencing the dynamic between national and state governments. Describe how the concept of federalism is reflected in the U.S. Constitution, providing specific examples from key amendments or clauses that establish the allocation of power and responsibilities.

Furthermore, analyze a contemporary issue or policy debate where federalism plays a critical role, stating how this principle contributes to the challenges or resolutions in that instance.