An odd loop

Several odd things have emerged with Attorney General Barr and the Mueller report. First, that a president cannot obstruct justice because they are in charge of justice. Second, that if no crime is proven, there cannot be obstruction of justice.
The problem with both those arguments is that they enable unchecked power and control. If a president can successfully interfere with an investigation, protect themselves from investigation of criminal actions, nothing can stop them. That leaves our country vulnerable to a president who would desire dictatorship. This would lead to elimination of the the three legs of democracy as the justice system would now be in complete control of the executive branch.
The congress' main job is to pass laws. While, on paper, they would still have that authority, without a separate and equal judicial branch of government, enforcement and interpretation of constitutionality of those laws would be in control of the executive branch.
The constitution provides a broadly worded oversight provision through impeachment for "high crimes and misdemeanors". Impeachment is, essentially, a congressional trial of a sitting president. However, if the executive branch can control investigation unimpeded, congress can be denied the factual materials required to make an assessment.
We are now in this odd loop that puts our democracy in a very precarious position. We've been there before but this time appears to be much darker and much deeper.
Never have we had a president who so openly admired dictators and totalitarian regimes. It's difficult to find a time in our history when so many of our people blindly accepted lies as truth or simply overlook the lies and wrong doing believing that some greater good is accomplished.
There is much that has happened over the last decades that have been eroding our democratic system. But this one is destined to put us in a loop that leads to total destruction of this great experiment.