Actually, the other half of the war was left there for the taking.
"suppose" whatever you like, LOL. I doubt that you know much about them at all.
Here's a snip that focuses on the small contingent of Legionnaires who were at DBP, all at one particular outpost:
.......Though hit hard, the Legionnaires rallied to the moment. A well-placed .50 caliber machine gun cut a huge swath in the charging enemy ranks. It caused enormous casualties. The Vietminh reacted swiftly and brought up a recoilless rifle team, which took it out with one shot. By now the fighting was hand to hand, vicious and bloody.
By now it was night, but the fighting continued unabated. With all that they had suffered by now, a lesser unit would have broken and fled. But this was the Legion. This was the same unit historically that had fought Rommel to a standstill at Bir Hacheim during the struggle around Gazala. They would continue the legend.
The Legionnaires would fight to the death. And they did. One by one, the radios on Beatrice went dead. The last message from the strongpoint was by a radio operator of the Ninth Company. He called in artillery fire from the French batteries on the command bunker and himself. Then there was total silence. Beatrice had fallen. The first of De Castries’ ladies had been slain.........
http://members.lycos.co.uk/Indochine/ops/dbpwilde.html
historically they have been "dirty dozen" types, who mostly worked apart from the reg French army. You confuse the two.
BTW, can you document that Legionnaires tortured vietnamese for sport? If so, I'd like to see it......your word alone isn't good enough.