" richest and most powerful country in the history of the world..."
not even close
http://en.wikipedia.org/wiki/List_of_pre-modern_great_powers
not even close
http://en.wikipedia.org/wiki/List_of_pre-modern_great_powers
The ancient empires had troubles feeding their populations at times. Today, most Americans are overweight.
Problem not solved: the population still has problems being fed the right things for their health to improve.
The British empire at his peak held one fifth of the worlds population. The Roman empire conquered everything was worth conquering and he was providing free food and gigantic games to his poor citizens. If you consider modern Europe his GDP is very similar to the US, although his political situation is more fragmented.
So back to the OP in each era the economic conditions improved, and there was a place where this improvements was more evident, a country who was richer and more powerful than the others. US is one of these nations but it's not something exceptional in history as the OP suggested.
The Han dynasty coexisted with the Romans, and I think they had a lot more people and land in their empire.
That's like saying that the last person on Forbes 500 is not really rich because they barely have 0.05% ($3 billion / $6 trillion) of the group's net worth.
"That's like saying that the last person (blah)"
No, because relative to other people, they have more stuff. The proportion they have of the group's net worth is significant greater than almost all other members, who have generally have five or more orders of magnitude less wealth (0.0000005% and less).
The reason why you're having trouble converting from countries to individuals is because there's currently only 200 countries, but 7 billion individuals. That's why the individual's percentage looks lower.
Also, your comparison makes absolutely no allowance for inflation. GDP rises for everyone over time simply due to inflation. Your shekel could purchase more in the time of Herod than it could in the time of Netanyahu. Zimbabwe's GDP went through the roof in recent years in their own dollars; but it didn't as a comparison to the rest of the world's output.
Of course, they might have been relatively more powerful in relation to their contemporaries, but that hardly implies anything relevant about the modern era.
US is the most powerful country now, but it isn't dominant (see Syria, Crimea, etc..) and it not as dominant as the British Empire or the Roman Empire was at their time
How many of those figures are of the US?
Not trying to start a pissing contest. Sorry.
As it's difficult to compare richness through history I was focusing on relative power. Can someone challenge US now? yes: Russia, China, Europe. Some past empires didn't have any counterpart because they were too powerful for anyone.
Economically, china is still not into high income yet, while Russia is stuck in a natural resources trap with lots of corruption. Europe is quite fine though.
Next time you intend to make a relative statement, use the word "relative". Of course, that was not what the post to which you responded was discussing, so your post would have been more obviously beside the point.
I agree that it wasn't the main point of the post i was replying to but I found that point just smug and incorrect, backed-up with cultural bias rather than historical fact.
EDIT: sorry, I wasn't clear enough, my comparison was mostly in the "most powerful" part rather than "richest"
It is interesting to note that in the 60 years that the US has been the ascendent world power, they've withdrawn from all sizeable wars with objectives unmet. If you're using actual active warfare as the yardstick, then the US is not powerful at all on comparison to historical powers. If you're using sensible measurements of power, then of course the US is powerful, most of it from projection of force and cultural/soft power.
Be careful with Europeans, they get pissed off easily. Slovenia has a GDP (PPP) per capita of $28,195. While that's half of the US it is actually a lot, they're definitely not subsistence farmers in Mali. You cannot really compare it with Moldova - $4,182. First world versus close to third world :)