How old is that map anyway, 3 to 4 years old ?
Because the Schengen borders are a wee bit different nowadays, and have been for the past 2 years (more or less).
The EU (taken as a singular entity) has roughly 30.2% of the world's GDP and roughly 7.4% of the world's population.
Of course, you will notice how the USA is listed as having 23.4% of the world's GDP (while barely having over 4.5% of the world's population), putting it as clear GDP leader if only individual countries are considered. However, a huge part of that GDP is largely _FICTIONAL_ since it only exists the same way Enron's profits existed, on paper (or, rather, electronically). This latest global economic crisis has had something to say about that.
Japan, on the other hand, has over 8.1% of the world's GDP and 1.9% of the world's population. Not sure how much of it is "real", but I tend to believe it's a far higher percentage than that of the USofA.
In stark contrast, China's GDP is estimated as roughly 7.2% of the world's GDP, but their population makes up 19.7% of the world's population. HOWEVER, one must not forget that while the USA is heavily into debt, with external debts almost surpassing the "on-paper" GDP (if it hasn't already surpassed it, either by growing debt or shrinking GDP)... and a huge portion of that external debt is held by China as USD reserves (as much as 10% of it, actually, and it's still growing). Sure, China could destabilize the USA economically, but fact remains, China's recent economic boom is heavily based on US consumerism practices (most of their exports go to the USA, and the largest portion of the rest to the EU), so they really have no good reason to even try to destabilize the US economy. Still, if things are headed the way it did the past few years, China might soon enough end up in a position similar to that of the USA.
Russia (noteworthy, it's no longer the USSR, if you combine all former USSR states into a single conglomerate, you get completely different results, but some of them are already as good as part of the EU, so it's a bit weirder) has 2.8% of the world's GDP and 2.1% of the world's population, which actually puts it (at least for the time being) in a far better position than China is in. Let's also not forget that they still have plenty of unexplored natural resources, as even without the former states they are still the LARGEST (by surface area) country in the entire world, with Canada being the second one right before China and the USA which are more or less tied for 3rd place... but both USA and Canada combined are barely a bit larger than Russia (again, the "smaller" Russia of today). Most of the EU is still heavily dependent on Russian natural gas, and the current Russian leadership isn't making it easy, especially as long as former USSR countries are being treated as good as being part of the EU.
So... yeah... the map, it's overly simplistic, overly theoretical and already out of date.
But yeah, on one thing I can agree... there can't be world peace, but that has nothing to do with GDPs and such things... it has to do with different governments. As long as countries exist, there will always be conflict. The only chance of "world peace" would be if the entire globe would be a single country, but there's no chance of that happening any time soon.