Why did america keep giving back the hill in vietnam?

Sounds like hill 875 (Dak To nov ‘67). It’s probably not that they had to give it back so much as there was no tactical advantage to keeping it.

I recommend you watch Hamburger Hill.

Here is a brief synopsis by Joe McMaster:

“Hamburger Hill is about the 101st Airborne division fighting in the Ashau Valley in the rugged hill country if Vietnam. It’s loosely based on the true story of the 101st taking hill 937 in May of 1969. This film is not your typical John Wayne kick ass macho movie. Instead it deals with several realities of war. Combat takes a heavy toll on the soldiers involved. When you add the fact that the soldiers were drafted and the war in many minds was not necessary. Plus a lot of the soldiers just didn’t want to be there. Hamburger Hill is an in your face look at close combat and the soldiers at a platoon level. The films covers the mental aspect of combat soldiers and one brutal battle that took place in 1969 in Vietnam. In the end we witness a slaughter for hill 937 that they won’t even hold if they can take it from the VC. A reality of war film that is a must see for any history or military buff.”

Why did they not keep the real estate they bought at such a high price. Too many reasons to give. A few are that they did not have the manpower to hold everything they took. Another is that sometimes it was just a strategic site that needed to be taken to facilitate troop movement or to be certain that you did not leave enemy behind you as you moved forward. Other times the powers that be had no interest in a muddy hill in the middle of a bunch of rice fields Mostly though, I think it was just because that was not the type or style of warfare that was being waged. It was a guerrilla war without front lines, fortresses or standing armies that faced each other for weeks or months on end.

Much of the Vietnam War was an illustrated case of generals “fighting the last war”. In WW II and to a certain extent in Korea (and most earlier wars, in fact), the strategy is to “take ground”, especially high ground where artillery can be fired for greater effect. (High ground permits better observation of more territory, and when used as a base for artillery it effectively increases the range of the guns because of the ability to “fire down” on targets.) “Taking the high ground” prevents your enemy from taking it to use it against you, so it has always been a generally favored tactic in war, and the Americans at first thought they were fighting a “classic” war.

However, the Viet Cong did not operate as a “normal” army that the generals were used to fighting, or at least “had studied in war college”. They VC never had much artillery, and since their forces were far weaker than the Americans’, they had to adapt to guerrilla warfare tactics, hit and run, ambush, etc. where their smaller numbers and reduced firepower worked to their advantage, since it’s much easier to hit fast and then retreat a small force safely (over ground that you know better than the enemy) than it is to fight a set piece battle with forces you don’t even have.

Consequently, they didn’t much care about taking the high ground to use for themselves, but they knew that the American forces would want it, and they made it attractive, at times, for them to attack and attempt to hold such strategic strong points… and then they would mount surprise attacks against those points, not so much to take them as to weaken the American resolve to fight at all.

So it was a favored tactic to lure the American generals into such places where they could “take ground” and look good to their superiors because they were “advancing the war effort”, but then they could be ambushed through the VC tunnel system, through paths in the jungles, and by co-opting the villagers that the American and Vietnamese armies had to pass through to attack and reinforce positions.

I don’t have anything to add to CW’s excellent answer, but just want to mention that you might be interested in the novel Matterhorn, which offers a detailed depiction of how horrible and frustrating it was to fight a war in that way. They kill themselves fortifying Matterhorn, then leave it to do other stuff, then come back to find that the VC took over their fortifications and they have to fight back in, and it’s all a result of upper command not having a grasp on the reality of the situation and trying to look like they did. It’s a gripping read.

They way I understand it, they bagged out and gave back absolutely everything in Vietnam.

I can sort of identify. They bagged out of the ME too.

Except the difference is, the Americans never went back to Vietnam.

We will keep going back to the ME.