Okonkwo as a integrating and disintegrating principle in things fall apart

Okonkowo is a uniting/integrating force not only because he is so acclaimed for his strength and heroism amongst the Ibo, but also because he epitomizes their values. His emphasis on hard work and stoic strength are values upheld by the Ibo, and so do they look to him as an example of a great man. However, he is also haunted by his own psychological demons - which start with shame over his failure father and are manifested in his murder of Ikemefuna - and these drive him too far. As the world starts to change, Okonkwo refuses to give up his extreme strength and his act of defiance against the Christians is not supported by the tribe. They worry such defiance will end them, and so they learn to adapt, where he will only bring them ruin by refusing to do so.

Also, even before the Christians show up, Okonkwo's blind allegiance to stoic strength ostracizes facets of the community who are more rounded or less sensitive, including his own son Nwoye.