After every war, indeed after almost any period of high feeling, there is a time of reassessment. "The Desert Fox" is Twentieth Century Fox's contribution to this period. Its thesis is that of Desmond Young's book on General Erwin Rommel. That is, it tries to show that Rommel, a fine field general in any Army textbook, was at the same time a fine man who came to hate Hitler, one whose political naivete finally led to his suicide to save his wife and son.

It is, undoubtedly, an interesting movie. Beginning with an unusual and active prologue, "The Desert Fox" flashes back for complete coverage of Rommel's life from the British breakthrough at EI Alamein to his suicide in 1945. James Mason, as the general, succeeds in portraying the character called for by the script. It almost appears possible for a man to be at once a hard, supremely competent Field Marshal and a confused, incredibly native politician.

Jessica Tandy, as his wife, has a comparatively small part but does extremely well with it. She turns what could have been a shadowy, unremembered character into a completely human, not so easily forgotten personality.

In documenting Young's theory on Rommel, however, director Henry Hathaway has sacrificed a good deal. First to get time enough to explain why Rommel behaved as Young thinks he did, Hathaway and Nunally Johnson, the producer, move too hastily through the Africa Corps' desert campaign. This made some of the book's best sections and certainly would have had high audience appeal. As it is now, the audience is likely to find the film's major portion less lively and less interesting than its beginning. The last three quarters of the movie are devoted to Rommel's inactive years preceding the Allied invasion of Europe and the few months beyond.

The most important sacrifices, however, are those that hurt the characterizations. Leo G. Carroll, as Field Marshal Von Runstedt, becomes a mellowed, quipping old officer, tired of arguing with his superiors. This is hardly accurate. At the same time Luther Adler overplays the part of an insane bombastic Hitler. A more subtle portrayal would have been more effective, certainly more believable.

Rommel, according to the story, first disagrees with Hitler over handling the Afrika Corps, and ends up taking part in a plot to kill the Feuhrer because he is so evil and insane. Rommel and his compatriots want to win the war, of course, but if they lose, they want to go down like good soldiers-not as murderers like their Nazi superiors.

This is a clear simple, theory, Perhaps the toughness of supporting it stems from this very lack of complexity; it is hard to believe that it was all so black and so white. Despite the director's sacrifices and the Desmond Young thesis, however, this is an above average picture and one worth seeing.