Answer:
Johnny links Dally to the Southern gentlemen in terms of courage. Dally may not have the same manners as the Southern gentlemen's but johnny says that he is as brave. Dally begins to show this when he comes face to face with his own death at the end of the book. The earlier discussion of the Southern gentlemen, shown as riding fearlessly to their deaths in war, it also can be seen as a form of foreshadowing.
He spoke out and asked for civil, economic, and racial rights. It was one of the most unforgettable speech's in history. The main purpose was to fight for the rights of African Americans/Blacks. Martin incredibly ended racism using only his words instead of fighting.
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He emotionally invested with everything, his emotions overcame him and he could not take it anymore.