It is surprising to see how differently the same basic idea can be phrased, though.
Joseph Goebbels, the unquestioned evil master of the art of political rhetoric, frequently gave a speech on the eve of Hitler's birthday. It is fascinating to read through them in order to see the arc of his rhetoric, from the triumph of 1933, where he portrayed Hitler as a great man, uninterested in the silliness of political celebration:
Today he has left the bustle of the capital. He left the wreaths and hymns of praise in Berlin. He is somewhere in his beloved Bavaria, far from the noise of the streets, to find peace and quiet. Perhaps in a nearby room someone will turn on a loudspeaker. If that should happen, then let me say to him, and to all of Germany: My Führer! Millions and millions of the best Germans send you their best wishes and give you their hearts...
to the one he gave on April 20, 1944, when it was becoming obvious Germany was losing the war:
Not only fortune, but also reputation is always shifting during a war between great men and nations. It is therefore difficult, perhaps even impossible, to determine the political and military importance of individual events in the midst of war. What yesterday seemed a brilliant move can within several weeks or months prove a major mistake, and that which seemed short-sighted and mistaken can later become a decision of deep wisdom. Only when a war is over, and usually some time after that, once its lasting results have become clear to all, is it possible to objectively weigh and evaluate its individual events.
That was true of every past war, and presumably of this one as well. The war can be evaluated only as a whole. Beside the events of the moment, a war has larger historical significance. Only a trained and practiced eye can understand that larger significance during the war itself. For example, consider the vast differences in Frederick the Great's reputation during the Seven Year War, particularly from 1760 to 1763. His personal reputation and that of his work during his day was influenced by partisan considerations, but today we evaluate him historically, that is, objectively and justly. His individual actions and decisions were evaluated in various ways. Given the circumstances of the time, some seemed to lead to victory, others to defeat. Even those in his entourage could not properly evaluate them.
A genius acts from instinct, sometimes consciously but often unconsciously, which raises his actions out of the ordinary sphere. Great, timeless personalities have to fulfill not only the tasks of the moment, but larger historical missions as well. Unfortunately, the two do not always agree. A war of vast historical significance brings with it the heaviest sacrifices and burdens. The less these problems are seen by people in their broader historical significance, the likelier the struggling generation will be misunderstand them, or even to think them avoidable.
This explains why those at the time and posterity evaluate historical events differently. We can think of numerous historical examples. We can hardly understand today why the contemporaries of Alexander the Great or Caesar or Frederick the Great did not understand their true significance.
To us there are no secrets any more.
In other words: "We will be vindicated by history."
A line we've been hearing a lot lately.
No doubt we will continue to hear it forever, in one form or another.
There will always be another war that is going badly for somebody.
Here is an excellent archive of Goebbels' speeches and writings that have been translated into English. It is well worth taking a little time to browse through them, if only so you can spot which modern politicians have, too.