F.E.M.A. and Hurricane Katrina comes to mind, It is not the federal Governments primary job, nor is it to superceed the State Government in directing desaster assistance. No government can be all things to all people that is the reason that there were to be different States reather than ONE country. So there could be 50 different opinions on a subject and still maintain a UNITED country.
States Sovereignty was not only pure genius, but also pure necessity, for the Unity of this country without the use of armed military force, or a police state.