I often wonder about the roots of this; of course 'the police' or 'America' have many faults, it's easy to point them out, but I'm always perplexed by those that can't see the bigger picture.
As though it needs to be articulated - the US doesn't really gain a lot from it's military expenditures, or '80 bases' around the world. But the world would be in chaos without them.
To start, 'high seas' (including the Suez Canal, the Gulf, and the Panama Canal) are currently open to anyone only due to US power. Particularly those 'strategic spots' - it is America that makes sure that anyone can use them. China, Russia, Iran - anyone. They're open, and free. The same cannot be said if antagonising powers like China, or local fiefdoms like a Panamanian populist to take over.
The entire world takes the concept of 'open, navigable waters' for granted, but this would not be the case were there not a force to ensure that this happened.
In Europe, the US is the only power preventing Russian Imperial expansion. Putin has already tried to 'pull a Crimea' in the Baltic states, it was only coordination by American-led NATO that enabled their defence. Even to this day, Europeans are very poorly coordinated on the issue. Ukraine would be fully under Putin's control, and Russia would be creeping into Poland. Georgia would have been invaded when the Russians occupied South Ossetia.
In Asia, we can see most recently the attempt by China to take exclusive control of vast ocean territories off the coast of Philipines, Vietnam etc. - only America has the power to ensure that this area will generally stay open.
S. Korea would not be a state without American power, it's possible that Japan would not, and certainly not Taiwan.
More contentiously, the US holds some authoritarian powers together, but even then it's for the greater good. Most obviously Saudi Arabia, Kuwait, but even Qatar, Bahrain, UAE fall in this camp. These aren't the nicest states, but they are generally 'good players' on the international scene, they mostly help fight against terrorism, and they sell their Oil on the international markets and market prices. Without US support none of those countries would exist as such. We saw what Saddam did in Kuwait, and there's no reason to believe he would have stopped there. In particular, the Iranians have been trying to very seriously destabilise those countries for some time by providing weapons, political cover, training, and support.
And that's just scratching the surface; without the US the high seas would not be open and navigable, the Suez/Panama/Gulf would be controlled by petty fiefs or hostile powers, large parts of Eastern Europe would be back in the Russian Empire and Putin would have that much more ability to antagonise, at very least Korea and Taiwan would not exist, and there'd likely be more hostility over there, and the Middle East would be unrecognisable, the hostilities would be far worse than they are today. And again - those are just the obvious areas - but if those dominos were to fall, so many others would. In short, a 'world without America' would be a dark and hostile place, there is no other leadership on the world stage that has the power to ensure the stability we have right now. Europe could, but they're not willing.
Americans gain a little bit in terms of prestige, access to some foreign markets, and their own security, but frankly it's just not enough to justify in hard terms.
Without the incredible goodwill of Americans the 'balance of internal political power' of their foreign policy would be such that they would have left the Japanese, Koreans, Taiwanese, Lithuanians, Polish etc. in the wind, long ago.
In the 1990s it was looking like the American led world order would melt into democracy, but it's not going to be that way at least for the time being.
FYI I'm not American.
The world is a very fragile, dynamic balance of power and the US is the only thing holding it together.
Despite many grievances, it's sad to see people fail to grasp this.