it was yonks ago that i ceased believing that the US President is anything other than a ceremonial role.....just for PR purposes.

other people are running the US, or not at all....if you look at the shyte-show they seem to make of most things.

Reagan was my realisation that looking the part, sounding good and smiling for the camera was all the job really entails.

Take the metaphor of a UK Royal being a head of the Navy or whatever other armed force.....they smile and rubber-stamp the decisions of their Admirals. And they would mostly barely know the front from the back of a ship. So long as they can find the drinks cabinet they are happy. Same with the Oval Office in the WhiteHouse.
The US will have an army of experts that sift through foreign policy, deciding who is friend and foe. Who to back and who to nuke......and the President could barely find Nogorno-Karabak on a map. Biden cannot find his underpants, Trump only needs to find a good packet of condoms.