So I was on the internet and stumbled this very educational text post written by Jacob VanWagoner on Quora.
His account: https://www.quora.com/profile/Jacob-VanWagoner
The original post: https://www.quora.com/Does-war-actually-make-the-technology-and-science-advance-faster
For your reading convenience, I copied the whole answer here, but I stress that I did not write a single word of this.
“Yes, depending on the needs of the war. I guess you could call it a silver lining.
Communications technology advanced due to war. Short-range immediate communication evolved from shouting commands to blasting a sound from a horn and can now take place by radio. Long range communications evolved from sending messengers on foot with a written message to training birds to carry messages tied to them, to transmission by telegraph and now via a globally connected network.
Communication security has also advanced. It went from easily-read messages to messages encoded with various decodable schemes like cyphers, to messages hidden by process technique like exposure to fire or acid, to today where exchange of keys and mathematical encryption based on randomness and are impossible to solve without getting the encryption keys.
Materials science has advanced through war as well. Starting with pointy sticks and rocks, to rocks hewn with sharp edges, to bronze and iron weapons and armor. Construction has changed with it, too, to allow more defensible and sturdy structures.
Our understanding of physical dynamics has improved thanks to war as well, starting with the first pointy-stick things being thrown through the air, to the addition of feathers to a small stick to make it fly in a consistent direction, then utilizing tension and leverage to make things capable of launching objects further and later mechanics to improve on the ability to use tension. Later came the faster ballistic weapons, starting with a metal ball being shot from a straight metal tube with exploding powder, to addition of rifling to make the metal ball fly straight, then on to shaping of the projectile and all the mechanics that went into automatically loading and unloading the projectiles and propellants.
Optics, too, from use of a telescope to see far away enemies and thus have an advantage, to now where we stick a telescope right onto a rifle with a crosshair that indicates where the bullet is going to hit.
Medicine advanced thanks to war, starting from figuring out how to save a wounded person from dying when something was jabbed in them, to discovering various poisons and how to cure them, and now surgical reconstruction or replacement of various body parts and treatment of infections.
And then there’s rocketry, which may never have been adequately explored if not for the desire to blow stuff up from afar, which is the key to our space infrastructure.
War has contributed to advancement in manufacturing technology, to hasten production of equipment.
Philosophy and politics have also been the beneficiaries of war. We have evolved from a position of “every able-bodied man must fight” slowly over to a position where most of the world believes a professional volunteer army is much better.
Everything that has convinced leaders that a person working on one thing or another will contribute more to the war effort than having that person physically be there to fight has put money and people on to those things in excess of what technology would have developed without them.
“It is well that war is so terrible, lest we grow too fond of it.”
-General Robert E. Lee”