Hmm whole thing feels like 40K has been squeezed into a political rant rather than an article about 40K.
I think quite a few need to stop using Blackadder goes Forth as the basis for their "facts" about the Great War. So very briefly
The tactics have been shown to actually be the best available at the time. Real modern military commanders have said this.
The ruling class actually suffered far more casualties proportionally than the working in fact this was the case generally up to this point as fighting wars/ protecting their subjects was pretty much the job of the nobility.
The Great War is considered the death, both literally and figuratively of the traditional ruling classes in both the UK and Germany and certainly the making of the working classes in the UK, as a class they actually came out of it healthier (the army fed them better) richer (the army paid them better) and more relevant (a power vacuum existed due to all the dead toffs)
Modern military training in the UK focuses very little on "doing it for your country " it actually focuses on fostering a bond between individual soldiers in a unit it's all about personal loyalty rather than loyalty to some concept. Also and I'm sure that Denzark will agree a lot more time and effort goes into not getting shot than it does into killing people. They even tell you "it's the other guy's job to die for his country". Far from being brainwashed killing tools the British army is a collection of cynical professionals it's why the US army doesn't like to leave home without them.
On the subject of all the Skulls completehook is absolutely correct.
CSM are in the whole very much NOT about dying for their gods, most of them Horus and Abbadon included don't even worship them. I fact the ones that do only do so really for the chance of immortality and ultimate power, something which the Gods of Chaos do actually provide (all be it sparingly)!and the emperor doesn't.
Also if people are on your ignore list you're supposed to be ignoring them telling people and going on about it makes you look like a passive aggressive prat.!