What would be your next move after shooting your commanding officer? You're a dead man yourself after that. Possibly even shot by your fellow soldiers who did drink the kool-aid. And your family back home would probably face consequences as well.

I wondered the same thing when reading about WW1 where soldiers were ordered to charge at enemy trenches and they'd predictably get mowed down immediately, then the officer would send the next group out. I can't help but think 'just shoot him', but it's a lot different actually being in that situation vs. reading about it