The tears trickled down her cheek immediately after she sang two words: “Gave proof.” Whether it just a neat bit of timing or her recognizing the history she made, it was perfect that Simone Manuel, standing atop an Olympic podium, a gold medal hanging from her neck, the first black American female swimmer to have won one, happened to melt at the precise moment in “The Star-Spangled Banner” that encapsulated her night.