I’m watching the rerun of the episode of MASH where a kid wanders into a minefield. The minefield was obviously laid by the Americans because Radar has a map of it (filed under B for Boom).
So, why does the 4077th have a minefield? Is it to keep the North Koreans/Chinese from knocking at the back door? I can see why they would want to cover the rear, but there is nothing to stop the enemy from knocking at the front door. They’re a non-combat unit. There’s another episode where an American artillery piece gets abandoned on their post and they start drawing enemy fire as a result. So, why do they need to mine the back when everything else is open?
Minefields are also notoriously difficult to remove, so if it was put there to protect some other base that has since moved, the 4077th’s just sort of stuck with it.
Actually the minefield was in the book, which the movie was based on. And the book was based on the experiences of the author at a real MASH unit. The book doesn’t say why the minefield is there, though.
Even in rear areas? The MASH units were typically deployed 20 miles or so behind the front lines, which is plenty far back to not be overrun very quickly (only the very fastest armored advances in WWII against light opposition covered that much ground in a day).
The front moved quite a bit. That minefield may have been laid months earlier as part of the front lines and left behind but marked on maps. Then the MASH comes along later and sets up next to it. Radar has a map because the army distributed maps of known mine fields to its own units to keep its own troops from walking in them.