On September 6, 1901, Leon Czolgosz shot President William McKinley twice in the abdomen in the Temple of Music at the Pan-American Exposition in Buffalo, New York. McKinley was shaking hands with the public at 4:07 in the afternoon. He died of gangrene on September 14.
Czolgosz had wrapped a handkerchief around his right hand and hidden a .32 caliber Iver Johnson revolver inside it. Nobody thought anything of the bandage on a hot day. When McKinley reached to shake his hand, Czolgosz fired. One bullet grazed him. The other went into his stomach and was never found.
The president seemed to be recovering. Then the wound turned. He died at 2:15 in the morning on September 14, and Vice President Theodore Roosevelt, then 42, became the third man to take the office through an assassination. McKinley had been the third president killed by a gunman, after Lincoln in 1865 and Garfield in 1881.
Men standing near the president had beaten Czolgosz to the ground, and McKinley told them to go easy on him. Czolgosz, a 28-year-old American-born son of Polish immigrants who had lost his job in the Panic of 1893, told the police he had taken his ideas from anarchist writing and acted alone. He was tried in nine days, convicted of first-degree murder, and executed in the electric chair at Auburn prison on October 29.
The lasting change was bureaucratic. Congress had never given the Secret Service, an agency built to chase counterfeiters, any formal duty to guard the president. It had been guarding him anyway, informally, since the 1890s. After 1901 the arrangement became a legal responsibility, and protection stopped depending on whether a president wanted it. McKinley had not: his secretary George Cortelyou had twice removed the Temple of Music reception from the schedule for fear of exactly this, and McKinley had twice put it back.