It isn’t rivalry when one service starts killing the other through bad doctrine, bad training , or just indifference. It’s a defect that needs resolution.
No service does that. NONE. Friendly fire has been with us as long as there has been fire, and NO SERVICE TAKES IT LIGHTLY. Not in the USA, at least.
Targeting pods and improved communication make fratricide less likely. It will never eliminate it. Targeting pods are a huge advance over dropping low with 3 seconds down the chute. It is even harder to do a level delivery accurately on the right target at 100’.
My SIL & oldest daughter were in the Marines. My son is in the Army. I was USAF, with 2 years on an Army fort and I deployed to Afghanistan in support of an Army project. I also did a 3 year tour attached to a US Navy squadron. I take perverted pleasure in having never had a joint tour, but having decorations from the Army & Navy to go with USAF ones.
Joking with each other around Thanksgiving is fine. Pretending “one service starts killing the other through bad doctrine, bad training , or just indifference” is horseshit.