>In 2021 the US had the its best opportunity to date to assemble a military tribunal to try and then execute a President
It's completely foreign to the US or the Anglo-Saxon world in general. The military as the final guarantor of state security is a continental European thing (and removing this has been the goal of many army reforms in Europe since the end of WW2).
This is a nonsensical reform. Every check and balance is itself a risk, nonetheless one can not build a safe Republic by removing them.
The US thinks it is the check for Europe but this offers no check for the leader of a superpower such as the US.
(It's apparently a flaggable offense to believe a legitimate republic is measured by making sense even if making sense goes against Anglo Saxon sensibilities since Cromwell.. I guess we can call time of death on the city on a hill.)
The modern anglo-saxon world has been pretty limited in this respect - but Charles I of England is an excellent example of pretty much just this playing out and being solved with a national razor.