As the conservative David Brooks writes in his latest column
When the World Is Led by a Child:
From all we know so far, Trump didn’t do it because he is a Russian agent, or for any malevolent intent. He did it because he is sloppy, because he lacks all impulse control, and above all because he is a 7-year-old boy desperate for the approval of those he admires.
That's really the best case scenario for Trump: he's not actively in cahoots with Putin, he's just very, very, very stupid.