Does Ralph understand why he must be killed?

Ralph had initially come to Jack's part of the island to work out some kind of peace plan. However, Ralph's realization that, in Jack's mind, he is a rival who must be eliminated becomes clear after the death of Piggy. Ralph realizes how savage Jack and his gang have become. That's why he runs away. Finally, after Samneric tell Ralph about Jack's plan to kill him, if he had any remaining hopes of making peace, he must realize the impossibility of making any sort of truce. That's why he turns and runs so quickly. However, Ralph's realization of Jack's true intentions are so slow in coming, that it takes the arrival of the British navy to save him.