You are presupposing your conclusion. It absolutely makes sense to compare freedom between countries, and these organizations have very detailed ways of doing it. In these comparisons, the US comes out looking pretty good, beating other first-world, western countries such as France, Portugal, Italy, Greece, and Israel.
The idea that "super-powers" are fundamentally different than all other countries when it comes to freedom is an argument you have made without support or evidence.
I made that statement without emperical evidence, since i consider it a logical implication.
Consider credit ratings: a few tiny nations have the highest ratings. But their combined assets represent nothing compared to the states. The US is rated lower, because the US is expected to fight its own fights. These tiny nations are rated higher, because the big guys are expected to cover their stability.
The same is true for my freedom: it is garantueed by the states, based on a sacrifice the people of my country would not make themselves. That sacrifice is huge: economic extortion of your social underclass to risk their life; the financial investments that leave very little of tax payers money for any "ordinary purpose" like education. And dont just look at your defense budget, your and mine security depends on your intelligence spendings just as much.
Remember WW2 where you saved our ass? The marshal plan were you rebuild my country? The war on Serbia, where you cleaned up our backyard? The war in Libia, where you allowed us to distance ourselves from a dictator we were doing bussiness with?
You have our back. In your shadow, we are not only safe from China or Russia, but even from ourselves.
But we get all that, without the sacrifice. We can be anti-war. We can spent all our money on education, rather than security. We can have freedom of the press, because our government does not represent any meaningfull stakes. Even our southern neigbours, Belgium. They did not have a government for more than a year. Imagine that!
If you guys would be truly free to vote in your own interest, to be informed correctly about that interest, to have true civil rights ... You would not be a superpower, you would be Canada.
For a short while that is, until China would invade, or the rich middle eastern countries would take full control.
Maybe i could phrase it like this. Your military are not free men. In a way, the US is the military of the free world. All of it: its media, its economics, its population. You guys (have to) live in a state of paranoia to keep that military machiene up and running.
The US is the military of the free world, and nations like mine, its (spoiled) free citizens.
Like most free citizens, we have a tendency to feel morally superior. We dont have to choose between security or liberty. You sacrifice your libery for our security, and most of us are completely oblivious to this fact.
The idea that "super-powers" are fundamentally different than all other countries when it comes to freedom is an argument you have made without support or evidence.