Yep some of the rsponses here are amazing. Of course he congratulated Obama. Obama is beatable. If Clinton were to succeed in stealing the nomination from him, being classy might attact some of the sitting out Obama voters to the GOP.
And it was thru a spokesperson, which is the minimum of what he could do.
He is the President, and this is an historical moment in our country, whether one likes it or not.
To not mention it would be bizarre.
Armchair quarterbacks....