IN THE LINE OF FIRE (1993) **** by Max Allan Collins (based on the screenplay written by Jeff Maguire) Published by HarperCollins, 1993, 262pp ISBN: 0-00-647856-5 Blurb: It was his job to safeguard the destiny of the nation. But at the crucial moment, Secret Service agent Frank Horrigan was a split second too late. Now, after a lifetime of…