In what way is Sanborn courageous in Gary D. Schmidt's novel Trouble?

In Gary D. Schmidt's novel Trouble, not only is Sanborn courageous for wanting to travel with Henry to climb dangerous Katahdin, he is also brave enough to defend Chay.In Chapter 22, while camping near the base of Katahdin, the two fishermenChay and Henry had seen in the chowder house in Portland, Maine, arrive in their pickup truck. They had been soldiers in the Vietnam War and had mistaken Chay...

In Gary D. Schmidt's novel Trouble, not only is Sanborn courageous for wanting to travel with Henry to climb dangerous Katahdin, he is also brave enough to defend Chay.

In Chapter 22, while camping near the base of Katahdin, the two fishermen Chay and Henry had seen in the chowder house in Portland, Maine, arrive in their pickup truck. They had been soldiers in the Vietnam War and had mistaken Chay for Vietnamese. Because they were so filled with rage from their experiences in Vietnam, they tried to attack Chay earlier in Chapter 13, but Chay, Henry, and Sanburn had managed to escape. Now, in Chapter 22, the two fishermen arrive again, having pursued the boys the past few days. One holds a shotgun; the other holds a broken bottle.

Sanborn shows bravery by being the first to speak in Chay's defense. One of the fishermen calls Sanburn a smart aleck, the fisherman saying he wished he could have been as smart as Sanburn but was pulled out of school and sent to "Vietnam to fight for my country against him," pointing at Chay. In retort, Sanburn defends Chay by saying, "No, you weren't," since Chay is from Cambodia, not Vietnam (p. 262). In this same scene, Henry is one of the first to act aggressively towards the two fishermen by grabbing from the boys' campfire a thick branch, burning at one end, and threatening the fishermen with the burning branch. Sanburn bravely does likewise, and both boys throw the branches at the men. Both men are injured, and the man with the shotgun fires at Henry; however, the man comes to his senses when he realizes he has just shot Henry, saying, "I didn't mean anything. We were just going to scare him. That's all" (p. 266).