In today’s world, the words “Secret Service” summon images of grim-faced gunmen sporting shades, dark suits, alert eyes, and set jaws. For the first few decades of its existence, however, the United States Secret Service had no such duties: The only presidents it protected were those printed or stamped on money. Created by an act of Congress in 1865 as a bureau of the Treasury Department, the Secret Service’s original mission was to protect the fledgling US economy by fighting the out-of-control counterfeiting of the nation’s currency. The federal government had only begun printing paper money in 1861, and within a few years, roughly half the bills in circulation were deemed to be counterfeit; this posed a grave threat to the US economy, since millions of honest citizens were being paid in money that was, in effect, worthless. Many of the best counterfeit bills, such as those created by master printers like Benjamin Boyd, could be spotted only by experts. Bank clerks were given special training to detect fraud, but this did not address the root of the problem. Congress’s solution was the Secret Service, which began as a highly specialized police force tasked with aggressively pursuing the counterfeiters themselves.