The war was fought, and won or lost from Washington. The codes used to transmit the highly detailed orders to us were broken by the Russkis with the help of the Walker Family Spy Ring, so the enemy knew my orders before I did, and the back-up orders. They knew our supply situation, our personnel dispositions, our innermost secrets. It was the greatest intelligence diaster which has ever befallen us. (Our true-blue FBI wasted 5 years and more during which, Walker's wife turned him in many times!)
Our upper echelon commanders squandered resources and did not make good use of intelligence, not believing for example, that the VC and NVA had hundreds of miles of underground facilities and tunnels through which they ferried men and supplies up the gates of Saigon, until late in the game.
But all in all, our war was lost in Washington because the Democrats refused to even declare war, and were terrified of Russian or Chinese involvement, so they allowed the enemy sanctuary and supply from neighboring countries, freedom to receive shipment from neutral countries, or combloc sources, and in general to engage and disengage at their leisure.
I was at Bien Hoa Air Base, and talked with an Air Force Major once. He was an A-37 pilot, and he told me that the Vietnamese always seemed to know when and where their air strikes were going to be. I just thought they had a good grapevine, but years later, I became convinced it could have been the result of the Walker spy ring. Those bas-----.