That's certainly notable, but not interchangeable with this one. The total size of your economy reflects certain opportunities for scale, regardless of your population and/or productivity.
If we think about corporations, when you have certain purchasing power, you can extract certain concessions from your vendors regardless of how many employees you have. When you manufacture and ship a certain number of products, you can profitably invest in infrastructure, again regardless of the number of employees you have.
I feel that the same argument extends to trade on the scale of countries. Which does not devalue the milestone you describe, just that they have different consequences.
Compare US to UK. California to Washington (state). EU to formerly more independent nations.
In each case the larger state delivers services less effectively, with more waste, arguably more corruption, and more useless nanny state rules.
Size is might, even if it's blundering, wasteful, and inefficient. (Although I am not saying the US is any of those things).
The question is whether or not might is good! (As in, is it better for your own government to be mighty or puny)
Many folks would rather live in puny Switzerland or Sweden than mighty Russia and China.
I faintly recall a study (by an Icelandic economist, if memory serves) which showed that Iceland had one of the lowest "corruption ratings" in the entire world! Perhaps I or the study are mistaken. Wouldn't be the first time.
The examples of corruption I'm thinking of are all related to the financial crash and Icesave scandal in Iceland.
Normally most people consider corruption to be some kind of private-public intermingling. But this was all about the public side trying to protect itself (I think?).
http://www.voxeu.org/article/government-failures-iceland-ent...
Not necessarily -- they are both important.
Consider how much impact the decisions of one central government in China have, now that they are the largest trading nation. You couldn't say the same thing about a small nation with high per-capita trade.
America didn't/doesn't have to fall to second place but we kind of did it to ourselves. We're going to be #2 in a lot of things, so let's get over it now.
I'm a bit leery of announcements like this since it's really hard to compare economies to each other (like comparing apples to oranges), but as a US citizen, I can tell you that I'm much more concerned about the state of our political system than our economy.