(Original post by Wahrheit)
US economy is still just under twice as big as China (nominal GDP) and also the US dollar is by far the most important currency in the world. Their global connectivity economically and also the level of technological innovation also contribute hugely to their economic strength.*
Their political system is flawed, but on the world stage they have the most political power. The US is the most powerful ally of countless countries and they have huge political sway.*
In the nuclear age, a war between any nuclear powers yields no winner. But in terms of how quickly a country can dismantle a smaller country, the US wins without contest. Their military expenditure is in an entirely different league when compared to other countries. Their naval superiority is unquestionable, with over half the world's aircraft carriers last I checked. Interestingly they don't have the best tech in all military areas though; for example, the US hellfire missile is a definite step-down from the UK's Brimstone. They have missiles and personnel stationed all over the world though, and at the press of a button could mobilise like no other country. Their military is honestly comparable more with the entirety of the rest of the world put together than it is with any one other nation.*
Great has subjective meaning to be sure, but I think global importance has to be a much more important factor than just niceness. San Marino might be a nice country, but it's clearly not in the conversation when talking about great countries of the world, for example.*
Well there's a whole other debate over which is more applicable, nominal or PPP GDP. I can't quite bring myself to make the effort over that debate, so we'll just agree to disagree. It's true that the dominance of the US dollar gives the US a huge amount of influence in the global economy....but.....it's a double edged sword since it's pretty much inevitable that the US dollar will not remain the sole reserve currency forever (already many nations are starting to diversity with the yuan, including the UK), and when it loses that status, the US's interest rate shoots up....and when you look at their debt.....not a good thing.
The US is definitely at the forefront of technological innovation....right now. But officially China overtook the US in patent applications a few years ago, and the trend going forward is that while the US will continue to be a major innovator without doubt, it will certainly have competitors it did not have 15 years ago.
Yeah, it's true that the US exerts a tremendous influence on other countries in diplomatic relations, especially with allies. That's undeniably true.
Not too sure the ability to 'dismantle a smaller country' is the best yardstick to measure the US's military strength. Ultimately those smaller countries are not going to be the major threats/challenges to US authority, influence and prosperity. It's the US's ability to fight the bigger boys that matters. And looking at recent developments, such as the Chinese submarine that literally surfaced right in front of one of the US's supercarriers, with neither it, nor its support vessels technology being able to detect it, in a clear signal that if there had been a state of war, that submarine would have sunk the carrier, I think US power projection is not unchallenged anymore. It's telling that when the Russian's deployed their S400 systems in Syria (the West has no equivalent system by the way), the US pulled its fighters, including the F22 out of the airspace now dominated by the Russians, and even admitted that Russian anti air and electronic warfare systems deployed in Syria were far more advanced that they expected. Now imagine if the Russians sold those technologies to those smaller countries. What would that do to the US's ability to project power?
I do think the standard of living at home is an important tool for projecting influence abroad. For example during the Cold War the Soviet Union was a vast and powerful state....that not many people wanted to move to. In contrast, the US had a superior standard of living and culture to the Soviets and that arguably was what won them the Cold War (increased exposure to the US standard of living led many Russians to demand the same, which led to the reforms that ultimately brought down the communist regime).