Well, I think that only one things would have happened, and that is Mr Churchill sacking Monty and replacing him in the middle of the battle. Despite of that, the Axis forces weren't able to break through, so the line would have remained the same way for a few weeks more. No Alexandria, no Cairo and of course, no Suez.

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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