Nobody ever proved Putin killed the journalist, nor has Putin said so.
Sounds like, in this context, Trump just wants to see more peaceful world relations.
As for Cuba, I have thought long and hard about that. There’s a point at which economic vengeance becomes pointless. It stank for the businesses that got taken over, but to put it crudely, this is just money. God can always get someone more money if He wants it. But a soul who has committed spiritual suicide, not even God can do something about this.
“The” journalist? He is suspected of ordering the assassinations of quite a few journalists, political opponents, and former agents. The guy is a KGB/FSB thug. It’s standard operating procedures for someone like him. KGB/FSB people are also masters of deception.