Just a character study on Chewbacca in the most pivotal scene of TFA. Features a bunch of throwbacks to the EU, because I'm still bitter at Disney for tossing out 30 years of lore into the trash compacter. I hope you understand.
A Debt Paid
When Han Solo died at the hands of his own son, Chewbacca was enraged.
Although he had spent most of his time away from his home planet of Kashyyyk, constantly in the presence of humans and droids and sentients lightyears away, he was still a Wookiee through and through. His dreams, his ideals, his morals all found their root in who he was as a Wookiee. And this death, this murder, this patricide stood against everything Chewbacca knew to be right.
Han is dead.
It was a tragedy that Chewbacca would not be the one to pay the life debt he had with Han.
From the very moment Han told his own superior to spare the Wookiee, Chewbacca would have done anything for Han: serve him, follow him, die for him. How much more steadfast could that loyalty be after almost 50 years? The fact that a glorious end had been denied Chewbacca was the height of dishonor.
It should have been me.
It should have always been him. At least in his mind, it had always been that way. Sometimes, if the warrior in him allowed him to entertain a flight of fancy, he would think of the most glorious end possible. He would be cut down by a legion of stormtroopers whilst roaring a song of battle. Or he could go out in a fiery explosion and obliterate an empire with one noble sacrifice. Planets, moons, and stars could shatter, and as long as Han and his family were safe, he would do it.
His family…
For Chewbacca the Wookiee, whose real strength came not from hunting prowess but from family and tribe, watching Han Solo's family fall apart was the most painful thing he had ever witnessed. He had begged, pleaded with Han Solo for the first two years to go back home, to try to mend, to not run away.
Chewbacca did not beg. He was known in the galaxy as a skilled warrior and feared Dejarik player (more so when he lost than when he won), and yet he begged, because this was a man who had done the same for him. But Han Solo ran away from him too, the coward. Even when they touched down on Kashyyyk for Life Day as they did every year, he ran from Malla asking him how Leia was doing, and from Lumpy asking if he could play with Ben. That was the only time Chewbacca ever wavered (if ever so slightly) in his life debt, seeing this broken man's cowardice. But honor trumped emotion in the end, and so he stopped asking. His family stopped asking. Han's family stopped asking.
Ben killed his own father.
Truth be told, Chewbacca could never see this man as Ben. To him, Ben was the baby he had spent many a naptime with, little fists curled up in his fur. Ben was Lumpy's little accomplice in troublemaking every Life Day. Ben was the boy who would not give up or stop halfway in anything he did, whether it was practicing his force powers or throwing tantrums. Chewbacca could come to no conclusion other than that this monster, this father killer was not Ben. When Han's body plunged down the shaft, Chewbacca believed that conclusion and fired, bellowing Traitor!
Now Chewbacca was not known for being the crackshot in the duo. That was Han, whose quick trigger finger and quicker aim had got themselves out of innumerable scrapes. Chewbacca was normally there to lay down suppressive fire, shots meant to be more dissuasive than pinpoint. Even so, he wasn't a bad shot. There was no way he could have missed that shot, not at that range. Not when Kylo Ren was such an open, stationary target.
But at the very instant he pulled the trigger the man who murdered his father was Ben Solo, son of Han and Leia, a second son to himself, and Chewbacca's aim faltered. Instead of busting a hole right through his chest, the quarrel exploded right at Ben's feet, knocking him down to the ground. He was definitely injured. With a bowcaster hit that close, he would have probably been hurt from shrapnel too. But he was still alive. And that was some relief to Chewbacca, because he realized that if he had hit dead on as he wanted, he would have been no better than Ben Solo. He would have dishonored Han and the forgiveness of a father that was in his final act before he fell.
It took the unmistakable sound of stormtrooper footfalls to give Chewbacca the excuse to turn away from that horrible scene. Because as grieved and wounded as he was in his heart, he still had a detonator on him and a command from the man to whom he owed his life, and he wasn't going to stop until that debt was paid in full.