Actually Stalin didn't trust much in the ULTRA...

And Kursk was not the most decisive battle of the Ostfront.

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"War is less costly than servitude, the choice is always between Verdun and Dachau." - Jean Dutourd, French veteran of both world wars

"A mon fils: depuis que tes yeux sont fermes les miens n’ont cessé de pleurir." - Mère française, Verdun