One doesn't fight in the hope of winning

That is the quote that Gary Wills, professor emeritus at Northwestern, uses to conclude his essay in the NY Review of Books.
It is a depressing thought, no?, to think that most of the time we fight the good fight not in the hope of winning it? So, what is the context in which Professor Wills writes this? At how much the change in the White House has not translated to significant directional changes that would indicate a move towards restoring the ideals of the constitution. The entire essay, which is not at all lengthy, is a great read. Excerpt:

A president is greatly pressured to keep all the empire's secrets. He feels he must avoid embarrassing the hordes of agents, military personnel, and diplomatic instruments whose loyalty he must command. Keeping up morale in this vast, shady enterprise is something impressed on him by all manner of commitments. He becomes the prisoner of his own power. .... He is a self-entangling giant.

.... in the nuclear era, the Constitution has become quaint and obsolete. Few people even consider anymore Madison's lapidary pronouncement, "In republican government the legislative authority necessarily predominates." Instead, we are all, as citizens, asked to salute our commander in chief. Any president, wanting leverage to accomplish his goals, must find it hard to give up the aura of war chief, the mystery and majesty that have accrued to him with control of the Bomb, the awesome proximity to the Football, to the Button.

But, we fight, not in the hope of winning because, as Professor Wills puts it:

Nonetheless, some of us entertain a fondness for the quaint old Constitution.

Yes. We do.