Well if the allied soldiers only saw the thing when it was near them, they could not shoot it as they would die. Goliaths where used on Utah beach and caused unintentional casualties. Their movement systems where damaged so the ran around the beach uncontrollably. GIs thought this was fun until one of them dropped a grenade in one, ran about 10 meters away, then got blown up by the explosion. His squad mates died also.

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Patriotism is where the love of your country comes first, nationalism is where the hate of other countries comes first.-Charles De Gaulle.