In 1780, John Adams and Samuel Adams helped draft the constitution for the Commonwealth of Massachusetts which says, "In the government of this commonwealth... the executive shall never exercise the legislative or judicial powers to the end that it may be a government of laws and not of men." By taking on the judicial powers of convicting and sentencing, Trump has turned our "system of laws, not men" on its head. This is the sort of thing you see in Erdogan's Turkey, but never in an advanced democracy.
Bill Barr and Donald Trump have committed a complete repudiation of one of the most important of the values and structures that made this country a democratic republic. Four brave federal prosecutors have stood up to this and resigned, but if there is not an overwhelming and systematic response to Trump's subversion of the American justice system, our republic is at an end. November may be too late.