I said this before, but I'll say it again. When Trump hosted Russian diplomats/spies at the White House, when he confiscated his translators notes after a meeting with Putin, when he had another meeting with Putin with no US translators present, when he left the Kurds high and dry, the press would ask, "why would Trump do this?"
Every time Trump did something inexplicable, there were always a range of explanations. However, there was one that explained them all.
There is a trail of circumstantial evidence he has been a Russian asset since 1986 at least. I suggest you read American Kompromat by Craig Unger.