The EU isn't like the US at all, it is separate countries with sovereign governments and the Eurozone isn't one combined economy, just multiple with a lot of tying factors bringing them to cooperate, which is really important to note. Besides, I can hear the constant bickering about the NHS, for example, from here. That said, if an administrative redesign could somehow raise benefits while massively destroying cost, I'd be all for it -- I'm just skeptical it could.
As for defense spending -- first you go out of your way to make a point about percentages of budgets and now you make a point about absolute spending? I see that stat over and over and over again, but it's important to remember that A. our GDP is... really really big, and a lot of industry goes into the military so that's more applicable than it would be with things like Social Security. It may be bigger than the next ten combined in terms of absolute money, but it sure isn't in terms of percentage. Not at all. And then there's another thing. One of the reasons we are so much bigger is because most of the top ten there is far lower than it would be if we didn't have their backs. That stat is only true because we support NATO, Japan, and South Korea.
But this is irrelevant to my earlier point. My earlier point is that cutting defense as the spending mainstay is very silly because it really isn't the big spending giant of the budget -- it doesn't even come close, and the size of other nations' militaries doesn't really affect this. Cutting defense spending wouldn't be all that effective, because it isn't that big of a percent of a budget compared to, again, entitlements, which are ever-increasing due to demographic trends.