Friendly fire – isn’t.
Recoilless rifles – aren’t.
Suppressive fires – won’t.
You are not Superman; Marines and fighter pilots take note.
A sucking chest wound is Nature’s way of telling you to slow down.
If it’s stupid but it works, it isn’t stupid.
Try to look unimportant; the enemy may be low on ammo.
If at first you don’t succeed, call in an air strike.
If you are forward of your position, your artillery will fall short.
Never share a foxhole with anyone braver than yourself.
There are many more, here.
One of my favorites that is not on the list and always holds true: The cover-up is always worse than the original crime...
Scrub, scrub, scrub...