It is very interesting to think about that coward at the tail end of some group of fighting men.

Yes, Wordwind, and it's even more interesting to reflect on the fact that at the very tail end of all those fighting men is a General safely esconced in his impenetrable redoubt - which reminds us all of this question so often asked by mourning mothers throughout the ages:

"Why do young men fight old men's wars?"

As to why "queue" is spelled "queue" and not "cue", one can ask why "quay" is pronounced "key".

The British seem to have a certain fascinating eccentricity about such things [perhaps because they think they invented the language]. Americans are less given to these embroideries. For them, a "Quay" is a "Key", not a "Quay", and they will not stand for "queues".

In fact, you can't even get an American to stand in a line-up any more [unless they happen to be in police custody, of course]. They can even buy their groceries with a digitized plastic card.