The night of his visit to the Ford Theatre, to see a play which would not finish, second-term President Abraham Lincoln was working on a plan to establish a Secret Service, not for the purpose of Executive Protection, but to protect and ensure against the circulation of fraudulent currency. That second duty is still on the Secret Service’s duty roster today, and explains why the agency was so long a part of the U.S. Treasury Department.

Confederate General Robert E. Lee surrendered to Union General Ulysses S. Grant and signed the Treaty of Appomattox on April 10, 1865. President Lincoln created the Secret Service to prevent rapidly growing counterfeiting as well as the continuing acceptance of some Confederate currencies on April 14, 1865. Lincoln was assassinated the next day, on April 15, 1865, by 26-year old John Wilkes Booth, a Confederate sympathizer and frustrated actor.

The Secret Service would not add the duties of Executive Protection for President’s and later former Presidents and still later Presidential candidates until after the assassination of President William H. McKinley in 1901. McKinley’s V.P., Theodore Roosevelt would become our nation’s youngest President, followed by his election to two more terms.

T.R., while making a third run for the White House in 1912, challenging his own hand-picked successor, William Howard Taft and the Democratic nominee, Woodrow Wilson, Roosevelt would be shot in the chest at a campaign rally in Milwaukee by a former saloon-keeper, John Shrank. Roosevelt survived the shooting, thanks to a 50-page speech folded in half in his suit coat pocket, as well as his metal glasses case. Candidate Roosevelt completed his 84-minutes speech, and prevented the near lynching of his shooter onsite before seeking medical attention. T.R. would surpass Taft, but split the GOP vote and help put Wilson into the White House.

After Roosevelt’s shooting, the Secret Service added protection for the President-elect and in 1915, the agency was given additional duties to investigate acts of foreign espionage (spycraft). In 1917, protection was extended to the entire first family. The Secret Service prevented assassination attempts against President Franklin Delano Roosevelt and Harry Truman. In 1962, protection was extended to the Vice-President and to former President Eisenhower, for a reasonable period, estimated then to be six months.

After the assassination of President John F. Kennedy in 1963, special protection was extended to his widow and children for a period of two-years. This protection was later extended to former Presidents, First Ladies and minor aged children for a period of four years. Following the 1968 assassination of Robert F. Kennedy, Secret Service protection was extended to major Presidential and Vice-Presidential candidates.

In 1971, the Secret Service picked up the responsibility of safe-guarding visits by foreign heads of state, and received its own 60-acre training grounds and compound near Washington. During 1972, Alabama Governor and Democratic Presidential candidate George Wallace survived an assassination attempt, without protection. And the Secret Service soon after twice blocked attempts to kill President Gerald R. Ford.

In 1984, the Secret Service received additional charges and responsibilities to investigate credit card fraud. During 2003, the Secret Service was transferred from the Department of Treasury to the Department of Homeland Security. In 2013, all former Presidents, their spouses and minor-aged children (up to age 16) were given lifetime Secret Service protection.

Donald Trump, as a former President and Presidential candidate, lands squarely in two of those protection categories. No one has done this since Teddy Roosevelt, when the agency was only four years into the role of protecting Presidents. However, as each successful assassination to date hasb reportedly been the act of lone wolf shooters, there still remain ways to reach that target.

And most recently, our U.S. Secret Service had multiple system failures in Butler, Pennsylvania, at yet another outdoor campaign rally by former President Trump.

This breach was large enough that the current head of the Secret Service, Director Kimberly Cheatle recently tendered her resignation. The Secret Service did successfully cover and remove Mr. Trump in a matter of seconds after he was shot. But as those shots came from behind and caused significant casualties and loss of life nearby, they clearly did not entirely have his back. Thank God for the Secret Service sniper who ended the short life of the shooter, Thomas Crooks, but in this moment of pause and reflection, perhaps in addition to a change in leadership, it is time to take the service back to its original purposes and roots, minus a few of more recent ancillary missions.