Part of what makes the Iliad such an immensely powerful work is that it renders a very challenging portrait of war. On one hand, war is shown to represent the vitality of human beings. Men, in particular, display their sense of honor and arete on the battlefield. Hector recognizes that he must fight Achilles, even though he recognizes clearly that it means instant death:
Now that my folly has destroyed the host, I dare not look Trojan men and Trojan women in the face, lest a worse man should say, ‘Hector has ruined us by his self-confidence.’ Surely it would be better for me to return after having fought Achilles and slain him, or to die gloriously here before the city....Better fight him at once, and learn to which of us Jove will vouchsafe victory.
War is shown as an exercise in which one's honor is best demonstrated. The very fact that war is brutal requires the greatest of commitments to one's honor. Homer seems to be suggesting that if it were easy, anyone could do it. It is for this reason why war is the ultimate test of one's honor. Homer constructs Paris as one without honor because of his incapability of fighting on the battlefield. Precisely because he cannot or will not fight, he is seen as without honor. War is the ultimate test of one's commitment to their honor, as seen with men like Achilles and Hector. War makes lesser men more honorable. Even though Patroclus is completely outmatched, his willingness to take up Achilles' armor and fight is what gives him a sense of dignity and honor. War becomes the ultimate testing ground for one's honor. Homer's rendering of war in the epic is that precisely because it is so agonizingly difficult is what makes it so special.
Yet, I think that it's a danger to see this as the only vision that Homer renders. Homer shows that war does not really solve much between nations. The ending of the epic displays this. It is not a valorous display of victory. The ending shows the Trojans mourning their own fallen son, while Achilles is not claiming victory. There might be a ceasing of hostility for twelve days, but the ending of the epic focuses more on how Achilles has righted a wrong done to Hector. His weeping with Priam is borne out of the consequences of war. The mourning he feels for Patroclus is matched by Priam's weeping for his son. The ending is one where war causes pain and hurt. There is nothing beneficial from it. Neither side is able to chalk its losses as "collateral damage." Both feel inexpressible longing and hurt. War is shown as a force that does not solve anything, leaving only singed and charred remnants in its wake.
Homer does not hesitate to draw a painful vision of war. The death of Patroclus, Hector, as well as the thousands of other soldiers would emphasize this. Homer is so deliberate in his depiction of war that he constructs an emotionally agonizing condition in war, as Hector experiences in Book VI: "He stretched his arms towards his child, but the boy cried and nestled in his nurse's bosom, scared at the sight of his father's armor, and at the horse- hair plume that nodded fiercely from his helmet." War makes children fatherless, while mothers and wives lose sons and husbands. Women become trophies to be violated, while civilizations fall. Homer does see war as a field to test honor. Yet, he also sees the destruction intrinsic to it.