I don't see how this is an attack on Sanders himself. Please explain.
It's pretty clearly a response to Sanders and the rhetoric of his army of followers. Don't play dumb.
Anyway, wonderful news! President Obama is the most effective liberal president in generations and anyone who suggests otherwise is incredibly naive, destructive, and counterproductive. Love seeing him fight back against these people hellbent on destroying the coalition that makes this party work, and makes liberal policy in this country possible.