> The US would fall apart very quickly if the federal government insisted on handing out loans and forcing the cancellation of aid and welfare programs in states that needed help the most.
I always thought that was the big difference between the United States and the "United Euro States"--the EU. The USA was founded "fresh" as a place in which states had a measure of independence but ultimately formed a nation at a federal level. That meant that it was in the nation's self-interest to help out states that ran in to trouble--paying off debts, etc.--because helping a state out would help the nation succeed.
The EU was formed with the baggage of centuries of bloody warfare among nations of wildly different and opposing cultures. I don't think that kind of history--and more importantly, the fundamental differences in culture--can be shrugged off in the 50-odd years that the idea of the EU has been around. It would seem that in practice, EU member nations are still very much about finger-pointing, and that can never lead to a successful federal bloc.
When a state goes bankrupt in the US, the other states pitch in at a federal level to solve the issue without divisiveness. When an EU member goes bankrupt, the other members demand blood.