Washington (CNN) -- "If we had been a split second slower, he could have been hit in the head." It has been 30 years since the attempted assassination of President Ronald Reagan. But for retired Secret Service agent Ray Shaddick, the memories of that gray, rainy day in Washington remain clear. It was 2:27 p.m., March 30, 1981. The 70-year-old president, barely two months into his term, exits the Washington Hilton after delivering a speech to leaders of the AFL-CIO. He walks out a side door to the hotel -- a door used more than 100 times by presidents in the previous decade.
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Thirty years after Reagan's shooting, presidential protection is more comprehensive
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Powerful explosives are among growing threats to presidential security
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Agent who shadowed Reagan: Explosives now "can take a city block out."
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Book author: "They don't want to risk agents thinking. They just have to act"
@placeholder walks on his own power through the emergency room doorway before collapsing.