Can a theater commander ever say that his war is not "winnable"?

[Fuchs]

Can a theater commander ever say publicly or to his CINC that his theater is not "winnable" (however that is defined)?

Is there historic precedent for making such an assessment?

Luddendorff told the German government that the war is lost and that peace talks need to be initiated (autumn 1918).

Rundstedt was asked by Keitel what could be done about the Normandy landing and he replied something along the lines of "Make peace, fools, what else?".

[Zack]

Luddendorff told the German government that the war is lost and that peace talks need to be initiated (autumn 1918).

Rundstedt was asked by Keitel what could be done about the Normandy landing and he replied something along the lines of "Make peace, fools, what else?".

Yep. The exchange is in the footnotes of the Rise and Fall of the Third Reich.

Rundstedt's dismissal may have come partly as the result of his blunt words to Keitel the night before. The latter had rung him up to inquire about the situation. An all-out German attack on the British lines by four S.S. panzer divisions had just floundered and Rundstedt was in a gloomy mood.
"What shall we do?" cried Keitel.
"Make peace, you fools," Rundstedt retorted. "What else can you do?"
It seems that Keitel, the "telltale toady," as most Army field commanders called him, went straight to Hitler with the remarks.....Kluge was immediately named to replace Rundstedt.

[rborum]

Luddendorff told the German government that the war is lost and that peace talks need to be initiated (autumn 1918).

Rundstedt was asked by Keitel what could be done about the Normandy landing and he replied something along the lines of "Make peace, fools, what else?".

Very helpful examples. Thank you.