A classic battle example was the Pusan perimeter from the Korean War, the NK had a staggering numerical advantage and pushed the US into the peninsula, the one

A classic battle example was the Pusan perimeter from the Korean War, the NK had a staggering numerical advantage and pushed the US into the peninsula, the one with a perfectly operating seaport, which we flooded with people, supplies, material, but the NK didn't have air superiority so the US mauled the NK logistics system, and a few weeks/months later the NK had to walk home with no ammo or food. Of course there are limits to that strategy as the Chinese proved that if you're willing to lose 20 to 1 ratio you can simply deploy millions of infantry and ignore logistics, admittedly most of them will die, and regardless of logistic support next thing you know we're back south at the original DMZ. The situation in Khe Sanh was similar, OK you're outnumbered 10 to 1 and surrounded, that's sustainable for months as long as the airdrops keep coming in. Of course Dien Bien Phu was an example where the airdrops didn't come in and the French were wiped out. After the war Gen. Westmorland was savaged in the press, Trump style, for making fun of Gen Giap for being the worlds most predictable one trick pony, but now that the politics and tempers have cooled its "OK" to admit the general only had one strategy that he used basically every time. Of course, in the end, it eventually worked, so losing 90%+ of your battles is OK if the enemy eventually goes home in defeat.