On March 30 1981, as Ronald Reagan paused to wave at reporters outside the Washington Hilton Hotel, six shots rang out. Instinctively special agent Jerry Parr hustled the seemingly unhurt president into his waiting limo, but as the car sped away, Reagan coughed up blood and accused Parr of breaking one of his ribs. At the George Washington Hospital, Dr. Ben Aaron looked at the blood flowing out of Reagan's chest, unaware of the bullet lodged just 3 inches from his heart, and faced the biggest decision of his life. If he performed an operation on the president's chest, he risked killing a 70-year-old man whose body was in shock and might not be able to cope with the trauma. But if he waited, a major blood vessel might burst, which could also kill him.