I dont think robert cuckman fundamentally thought this far when it comes to his writing but mark is a great reflection for how society views heroism. spoilers ahead and stuff, after getting involved in 'just war' betraying his own people for the sake of a vague goodness. he comes home to find the woman he loves has killed his child, gotten fat, and he has to bear the knowledge that the foreign evil that he has been continuously punished for fighting against has entered his home and is now actively integrating with his people and subconcious gun is constnatly held to his head by the fact that the leader of this great evil is far to powerful for him to ever beat in a fight and that he has no choice but to stay silent. Along with the fact that the very same people who actively enlisted him in this war now actively plan to poison his world killing him and the entire population of who he loves. fundamentally he knows that their is no god or heaven in his world either meaning that some grandeur good doesnt exist and this is simply one foreign group vs another foreign group.
mark is the modern 'good man' = an emasculated traitor who is incapable of protecting those around him, is actively manipulated by those smarter and more cruel than him. relies on evil men to actively not enforce their will on him, is incapable of protecting his children or woman, is destined to love a fat pig of a wife and has to betray his own people in order to be considered good all while the determiner of good is either in active or doesnt exist. BRUTAL