Mainly the brutality of it all, the amputations, mortality, and prisons. Also the war brought death to a population that was thriving economically because of the slow brutal process of slavery, maybe it produced a small amount of karmic retribution.
There also is a push in transportation as mechanical evolution happens faster when lives are on the line. Naval vessels were produced often with metal when speed wasn't an issue, and when it was the Confederate blockade runner ships did a great job, and produced men like Rhett Butler.
Railroads were run 24 hours a day often moving supplies and men, a great advantage of the Union army who employed men of the biggest companies of the day like the Pennsylvania railroad's Thomas A. Scott.
But I would like to focus here on the Mule, a true brute of efficacy. If I had a bicycle company I would produce a tough steel commuter proletarian oriented bike called 'the mule'. When I learned in my younger years of the Mule, from the epic television series Grizzly Adams, which showed off a mule named '#7' who was often referred to as a burro (donkey in espanol). A mule is sterile, a offspring of a male horse and a female donkey. Not to be confused with a Hinny, which is the offspring of a female horse and a male donkey. Civil War Mule usage is documented here.
Now to segway, mules are beasts of burden and have been with humans for quite some time. but the are almost always infertile, excepts in rare cases. Why do they exist? Are they as cool as Street Sharks?
Will sharks one day be a species filled with asexual reproduction?
None of these matter,but if questions of Darwin were pointed to examples like the Mule, and shark reproduction, wouldn't his teaching gain a resurgence like the Fonz when he jumped the shark. Its asking to much for people to think and pay attention, unless others are. I care about Bristol Palin on dancing with the stars because others do, I heard customers at the restaurant talking about it so it must be important, just like the weather.