He's mad Obama called him a jackass and didn't apologize.

He thinks, gleaned from his statements, that Obama didn't magically fix whatever issues exist in Chicago due in part to his actions.

He's mad Obama left after one of his performances and didn't speak to him.

Couple that with Kanye's ignorance of exact Trump policies that he agrees with and this is just one big public tantrum.

This whole thing is one big public therapy session for Kanye and it sucks to see him like this.