It has worked due to the treaty being worked out in early cold war, when both East and West were already planning military operations and bases in Antarctica -

It has worked due to the treaty being worked out in early cold war, when both East and West were already planning military operations and bases in Antarctica - that way, neither side could have it and they were fine with it, sparing a considerable expense. It has held in place since then by both inertia & similar "if I can't have the resources, no one can" and other resource sources still being usually cheaper to mine.