Could the u. s. armed forces be successful without support from the homefront?

Sometimes. It depends on whether you are speaking of conquest or occupation.

If you mean conquest, then other than supplying the arms, the home front is of little direct value. The armed forces do most of the fighting and dying and other than morale and the supply of weapons, those at home can do nothing much.

If you mean occupation, that is a whole different problem. Now the civilian population must agree to supply what is needed to make sure the troops are in good condition to carry out their mission.

That problem of siege (which is a form of occupation) nearly destroyed the German army at Leningrad. The home front made great sacrifices to supply the army. The Russian People also made great sacrifices. It was a very nasty part of WWII.

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