Cavalry became obsolete with the widespread adoption of cartridge rifles.
Horses remained valuable for transport through WWI, and were used extensively through WWII by Germany and others.
But as a fighting force, cartridge rifles made horse cavalry obsolete, as the cavalry charge became a suicide mission.
In 1942 an Italian cavalry unit charged a Soviet army unit armed with Katyusha (Kathy) rocket launchers—and won the battle.
Yup, and there’s an old saying about that, you go to war and may get your ass shot off with the army you have.
The basically universal adoption of tractors for farm work in this area was delayed by WWII. There were of course those who had changed over, but tractors were hard or impossible to get in the early 1940s. I remember someone saying to a much younger me that Ford was first to introduce live power (where the PTO runs all the time) right after the war. That kind of checks out, the small tractor my late father used didn’t have it and was made in the 1930s. He sold it in the ‘90s, but there’s reason to believe it’s still in use.
A building that still stands on a major street on the NW side of Grand Rapids was a saddle livery shoeing place until the mid-1940s, because travel by horseback or horsedrawn was still happening during the war years.
Well, I guess I went on a bit.