The problem is that you're saying it's very hard to measure wealth while at the same time confidently claiming the US is at the top. That just doesn't make sens

The problem is that you're saying it's very hard to measure wealth while at the same time confidently claiming the US is at the top. That just doesn't make sense. GDP may not be a perfect measure of wealth but it's the best we've got IMO. I've lived for a short while in Canada, for many years in Australia, and visited the USA many times... I really don't see much difference in wealth in general. I'm sure there's a lot more extremely rich people in the USA, but those are a small portion of the population so I wouldn't consider that an important indication of the wealth of a country, at least not as much as the wealth of the majority of its citizens (and the USA notoriously also has a lot more very poor people than either Australia or Canada). If you do that, perhaps the Arab Emirates would be wealthier? Or even China, home to more bilionaires than the USA IIRC?! Also, if you include healthcare access and pension as you seem to be doing, again, the USA is probably the worst as you're pretty much on your own with those things, while in nearly any other developed country, people get decent healthcare and pension even without having had high paying jobs their whole life.