When the RMS Titantic sank on 15 April 1912, the greatest tragedy is that the ocean liner had far too few lifeboats to accommodate its passengers and crew. In an attempt to solve this problem, the United States Congress passed the Seamen's Act, which, among other things, required each ship to provide enough lifeboats to accommodate the maximum number of people that could board the ship.
The new law required all existing ships to be retrofitted in order to be in compliance. The additional weight of the added lifeboats caused the SS Eastland to be unstable. On the brink of its first voyage following the addition of lifeboats, with its full contingent of 2,752 passengers, the Eastland groaned sharply toward its port side and rolled into the river. Of those on board, 844 perished.
Was it the proper role of the federal government to ensure that all ships have enough lifeboats? In my opinion, no.
When the federal government makes a mistake, that mistake must be borne by all Americans. When an individual state makes a mistake, the same mistake may be avoided by other states who learn from the lesson. Additionally, decisions that are made on a more local level will be likely to involve people who understand the potential ramifications of those decisions--such as shipbuilders.
So, the next time you think "There oughtta be a law!", think about who should make that law. Chances are, it shouldn't be the federal government, because chances are, when Congress overreacts in order to make something safer, it can actually make it more dangerous.