How does a nation ensure that "this should NEVER happen to a President again!"?
By demonstrating to the public the full extent of punishment, for the highest crimes in the land.
What is the full extent of crime and punishment? Treason. Murder. Life imprisonment. Death by execution. All public.
There is only one way. The ultimate deterrent. To put the fear of God in anyone who ever tries to overthrow the republic again.
This will be followed by a radical reformation of corrupt institutions and organizations and a general "new awakening" of hidden truths, in order to preserve and maintain the constitution, freedom of the individual and the rule of law.
Humans have a true destiny. They tried to keep us all as slaves.
This is worldwide.
Prepare.