It's definitely the most powerful. No one else is even close in raw military power.
Yes in world terms he's clearly very powerful. Compared to the rest of the world a single US aircraft carrier or ballistic missile submarine captain is more powerful than most world leaders.
But his power is very limited. Congress can remove him, they can even completely defund the military if they wanted to.
It's a completely different discussion topic as to if we have the most powerful military. We have a lot of resources sunk into using aircraft carriers to project force around the world, and the current generation of carriers have not faced the current generation of anti-ship missiles.
We have current generation anti-ship missiles as well. So let's say that in a full scale war all surface vessels are gone, and let's say there are no nuclear exchanges.
Our submarine fleet and long range bombing ability are still far superior. Russia and China have near zero force projection capability. Even with surface ships gone, we still have more.
Russia and China both accept that they can't match the US, and all of their strategies for war with us are defensive strategies designed to make it too expensive for us to bother.
No one seriously doubts American military dominance today--not even potential rivals.
It's definitely the most powerful. No one else is even close in raw military power.
Yes in world terms he's clearly very powerful. Compared to the rest of the world a single US aircraft carrier or ballistic missile submarine captain is more powerful than most world leaders.
But his power is very limited. Congress can remove him, they can even completely defund the military if they wanted to.