I wasn’t fully convinced before that Putin has Trump in his pocket, but after that stunt, I am convinced that he is under Putin’s thumb. Trump and co. could have had marching orders from Putin to do exactly that. Also, this is something that Putin have done and would do, publicly humiliating someone on live TV.
He campaigned on it the first go round. His actions also during that presidency reflect it - remember he was the one that brokered the awful deal with the Taliban.
He cozies up to dictators because he doesn’t want to fight them and he abuses our allies because he knows they won’t fight the US, which he thinks gives him leverage.
Or as I’ve heard it, he speaks loudly and carries a little stick.