Once the Confederacy started the war then Greeley was supportive of the war effort, if not always supportive of Lincoln's actions in pursuing it. In may ways Greeley was far more blood-thirsty than the Southern supporters paint Lincoln as being.
I am reminded of an incident between Hitler and his Architect, Albert Speer. When they were designing some piece of architecture that was intended to be a reflection of Hitler, Hitler said he wanted it to be some ridiculous size, to which Albert Speer replied, "No My Fuhrer, it must be bigger!"
Toadies are always massaging the egos of their masters. Once Lincoln's men made certain whom Greely must answer too, he became a good little propaganda organ.