The suspect detained following a shooting incident at the White House Correspondents' Association dinner is believed to have breached the outermost layer of security at the event because he was a guest of the hotel, officials said Saturday. Security for the annual event, where Donald Trump was due to speak, is always tight when the president attends, especially given the venue’s history. The Washington Hilton was the site of an attempted assassination of President Ronald Reagan 45 years ago, and law enforcement argued that their “multi-layered protection” worked as designed. Still, the incident is sure to set off more questions about security around the president and political events in the wake of high-profile acts of political violence in recent years. Here's what we know about the security of the correspondents' dinner.…