Reply #10: WW2 was really, really, really, really, really huge

[Posteritatis]

Korea and even Vietnam were slap-fights compared to the Second World War.

It's difficult to overstate the scale of that war. Nothing - nothing - of that scale had ever happened before or since. (Nothing of its scale likely will ever happen, either.) The United States had more than sixteen million people under arms by the end of the war, and that number was showing no signs of peaking by the time Germany surrendered. Sixteen million! They were kept in food, water, medicine and ammunition surprisingly well, given the sheer number of people. Until Japan went down, people were expecting the war to last into the late forties or maybe even 1950, and were planning accordingly.

If you have enough weaponry to arm sixteen million troops through some of the most intense fighting in human history, you're going to have a surplus for a long, long time, especially for things like small-arms ammunition.