That book is extremely pro communist (hence the title). This is a pretty poor take on the war for several reasons, not least of which "maximum military effort" and didn't use most powerful weapons are somehow in the same sentence. They literally did not use their maximum military effort (not just on the atomic bomb front). It was a political war full of mishaps that were capitalized on by North Vietnam. I also thought PRC and Russia backed North Vietnam which seems relevant. The general point that military might isn't the sole determinant of a wars outcome is true and important -- and also pretty obvious.