As the Supreme Court has consistently ruled in the past, the Constitution gives Congress only limited and enumerated powers. However vexing a particular problem may be, Congress can address it using only those powers. If its preferred solution requires the exercise of a power it was denied, such as a general police power, then Congress must think again. If, as in this case, Congress persists in adopting legislation that goes beyond its constitutional authority, the courts must invalidate it. That is not judicial activism. It is the fulfillment of the judiciary’s constitutional duty.