Discuss the importance of Brian's major breakthrough in "Hatchet."

I would pose another breakthrough for Brian.  I think that enduring the moose attack and the tornado are significant breakthroughs for Brian.  He does not cry nor does he give into unehealthy displays of anger, as had been seen earlier in the text.  Rather, he is shown to be quite composed in focusing his energies in rebuilding his surroudings and recommitting himself to his life in the wilderness.  He is not shown to be broken or upset despite the fact that the moose attack was fairly severe and the tornado was, well, a tornado.  With both of these incidents, the wilderness threw its very worst at Brian.  Yet, he presents an extremely tough will to survive and refocus his energies in survival.  I would pose this as a major breakthrough because it reflects Brian to have become one who has become part of his surroundings, and not rebelling against them.  Brian's character is revealed to have shown its most complexity and strength at these points.  All of his successes thus far have been small breakthroughs, but they seem to have been leading to this point of emotional maturation and personal strength.  Given where he was when he crash landed in the Cessna from where his character is when the moose and the tornado hits, I think that his character has displayed an intense breakthrough.