Robert Mueller

One of the reasons Mueller had difficulty determining how direct the contacts were between members of the Trump campaign and the Russia state apparatus, was that they were looking at that state apparatus as if it was part a traditional nation-state. That was a major mistake, as Russia has morphed into a "Mafia State" since the collapse of the old Soviet Union. The relationship between major figures in Russian organized crime and the Putin regime is complicated and Trump has had decades to build these relationships. The whole thing was beyond the limited scope of the Mueller investigation.