The most devastating of all wars for the United States was the "Civil War"..1861 to 1865..Largest % of deaths ever.

[Stuart G]

Above is A "Little known Fact...Why? because it happened so long ago.....and
".rare medical help and incompetent medical help and procedures. "

[RockRaven]

1. Many other factors contributed to that high percent, compared to our other wars.

Duration.

Neither belligerent needed to transport forces across a sea/ocean.

Persistence was existential for at least one party.

[TexasDem69]

2. Along with poor military tactics

That didn’t adjust for the weaponry.

[Former3rdCommittee]

3. The Civil War is only twice as long ago as World War II

1944 to 2024 is 80 years.

1864 to 1944 is 80 years.

[mucifer]

4. President Lincoln had some REALLLY bad generals. It was so sad.

[NNadir]

5. There is an interesting monograph which I happen to be reading, on medical developments in the American Civil War.

This is it: Civil War Medicine: Challenges and Triumphs by Alfred Jay Bollet. Galen Press (2002).

Dr. Bollet's contention is that although the war was horrible, during it, many advances in both treatment and logistics improved the care given to wounded soldiers and, in fact, the event led to advances in medical care in the 19th century, particularly with respect to surgery.

I've only read a little of this book thus far, but I suspect that it will go a long way to addressing many misconceptions that medical treatment of wounds was merely bungling butchery.