Helplessness induces hopelessness, and history attests that loss of hope and not loss of lives is what decides the issue of war.
—Basil Liddell Hart. The Real War, 1930.
All humanity being a giant extended family, fratricide must be kept to the absolute minimum. Sometimes retribution will require otherwise, but that aside, military objectives should be achieved with the least amount of bloodshed possible. For example, if a military target is to be bombed, then a precision-guided paintball should be dropped twenty minutes before the real bomb arrives. Civilian casualties should be avoided wherever possible. Enemy ships should be attacked with smart torpedoes that attach thermite collars to their propeller shafts. Submarines should release masses of inflatable lifeboats after sinking a ship.