Washington, D. C., January 26, 1863.
GENERAL: I have placed you at the head of the Army of the Potomac. Of course I have done this upon what appears to me to be sufficient reasons, and yet I think it best for you to know that there are some things in regard to which I am not quite satisfied with you. I believe you to be a brave and skillful soldier, which, of course, I like. I also believe you do not mix politics with your profession, in which you are right. You have confidence in yourself, which is a valuable, if not an indispensable, quality. You are ambitious, which, within reasonable bounds, does good rather than harm; but I think that during General Burnside's command of the army you have taken counsel of your ambition, and thwarted him as much as you could, in which you did a great wrong to the country and to a most meritorious and honorable brother officer. I have heard, in such a way as to believe it, of your recently saying that both the Army and the Government needed a dictator. Of course, it was not for this, but in spite of it, that I have given you the command. Only those generals who gain successes can set up dictators. What I now ask of you is military success, and I will risk the dictatorship. The Government will support you to the utmost of its ability, which is neither more nor less than it has done and will do for all commanders. I much fear that the spirit which you have aided to infuse into the army, of criticising their commander and withholding confidence from him, will now turn upon you. I shall assist you as far as I can to put it down. Neither you nor Napoleon, if he were alive again, could get any good out of an army while such a spirit prevails in it. And now beware of rashness. Beware of rashness, but with energy and sleepless vigilance go forward and give us victories.
Yours, very truly,