In 1984, Congress passed the National Minimum Drinking Age Act, making it illegal for anyone under the age of 21 to purchase or possess alcohol in public, but technically there's no such thing as a national drinking age. How can this be? Setting a national drinking age falls outside the scope of the US Congress' constitutionally-enumerated powers; it has historically been a state issue.By putting the national drinking age in the Federal Aid Highway Act, however, Congress didn't require states to enforce a legal drinking age of 21; it just made that a condition for continued federal highway funding, so if states wanted to keep federal dollars for their roads, they would have to comply with the new national drinking age limit.

In 1987 South Dakota, which allowed 19-year-olds to purchase beer containing 3.2% alcohol by volume or less, challenged Congress' law in court. The Supreme Court took the case and determined that it was constitutional for Congress to use financial penalties to influence state policies so long as the penalty meets certain legal requirements such as being unambiguous and promoting the general welfare.

Since then, the federal government has been able to maintain a national minimum drinking age of 21, but all that could now change with the Supreme Court's recent health care ruling, The Daily Beast reports:

"Seeking to make more people eligible for Medicaid, Obamacare gives states two options: take more money from the federal government to put more people on Medicaid; or lose the federal funding they were already getting for the low-income health-care program. The Supreme Court ruled that threatening to take away a state’s Medicaid funding unless the state does what the federal government wants is “unconstitutionally coercive” and declared it invalid."

So if taking away a state's Medicaid funding unless it meets a federal requirement is coercive and unconstitutional, it's not a major leap for states to start challenging the strings attached to other federal dollars as unconstitutional on the basis of this new Supreme Court precedent, including No Child Left Behind's strings attached to federal education funding and even the minimum drinking age string attached to federal highway funding. The result could be lower drinking ages than 21 across the nation and drinking ages that vary by state.

Conservatives, while opposed to the Supreme Court's decision to uphold the individual mandate, have hailed this part of the ruling as a major victory for the states and the federal concept of government implemented by our nation's founders wherein the power to make and enforce public policy is shared between a more centralized and more local governments.

What do you think? Should states be setting the minimum drinking age, or is federal policy here constitutional? Is the current minimum drinking age of 21 too high or just right?