“One is, I’d say it’s ethical,” he says. “It’s solidarity, the European project.”

His other two arguments appeal more to self-interest. Without further fiscal integration, geographic adjustment in the eurozone will have to lean on labor mobility. If the Greeks can’t get safety-net payments financed by Europe-wide taxes, many of them will just move to places like the Netherlands, where they might be able to live better even if their Dutch isn’t very good. Additionally, he argues that fiscal integration will promote greater economic equality, and therefore greater macroeconomic stability and fewer crises.

These arguments, or arguments like them, have carried the day in the United States. You could just as easily ask “What’s in it for Connecticut?” and yet voters and officials in states like Connecticut express little desire to unwind the fiscal union; the strong sense is that we’re all Americans and we’re in this together.

For better or for worse, this is not the prevailing attitude in Europe.

The ethical argument for fiscal integration is undermined because Greece and Spain are actually not so poor. If countries like the Netherlands are going to give away their wealth to needier places out of ethical obligation, there are more deserving recipients outside the eurozone. Greece is not even the poorest country within the eurozone, which is why arguments that fiscal integration is ethically necessary are met with skepticism in relatively poor countries like Estonia and Slovakia; they fear fiscal transfers will flow away from them toward countries that are richer but more profligate (i.e., Greece).

Then there are the arguments from self-interest. A more economically integrated Europe would be more economically stable because it could respond more effectively to crises like the one in 2008. That would certainly lead to higher economic output in places like Greece. But would it really mean better economic performance in already high-performing countries? It certainly feels counterintuitive to tell a wealthy, well-governed country like the Netherlands or Austria that its economy will become more stable if it becomes more integrated with Greece’s.

Further, an economic union can promote economic stability only if it is politically stable, so market participants can have confidence that fiscal transfers and bank guarantees will remain in place. Magnanimous attitudes like the ones expressed by the people of Connecticut (or a lack of awareness about how many of their tax dollars are being spent in other states) aren’t just necessary for the adoption of a fiscal union; they’re a key to making it work over the long run.