Former Fox News personality Geraldo Rivera opened up to MSNBC’s Ari Melber on Tuesday about the thought process that caused him to break from former President Donald Trump, whom he has known for years, to endorse Vice President Kamala Harris. Rivera made this endorsement in a lengthy post to X earlier this month, calling Trump a “sore loser” who was a threat to the Constitution. Asked about this by Melber, he delved deeper. “What you say also matters and how you say it and who you say it to,” said Melber. “Tell us about what you were getting across there and why you went beyond the usual, hey,…