The Watergate incident made Kakashi suffer greatly. An episode.

Episode 339. According to Youku.com's inquiry, kakashi gaiden in Naruto episode 339, on his first day in Hatake Kakashi, when he and his teacher Namikaze Minato performed the task of the bridge without god, Kakashi became forbearing. For Kakashi, forbearance is also his lofty pursuit of his father's white teeth. On the day he became a teacher, his teacher gave him a gift with the words "Bitterness" written on it. It was this bitterness that saved Kakashi and Lin's life at the last minute. Namikaze Minato came back from the distant battlefield to save them.