At times, the US Secret Service has resembled a bunch of pistol-toting frat boys on a taxpayer-funded spring break. In the words of a drunken supervisor speaking to his men in the run-up to a 2012 summit in Cartagena, Colombia: “You don’t know how lucky you are … You are going to fuck your way across the globe.”

Disturbingly, the debacle in Colombia was not a one-off, as Carol Leonnig makes clear. Rather, it was the most glaring episode in an accumulation of horribles. Six agents were dismissed, another six disciplined.

Leonnig knows of what she writes. She won a Pulitzer for her reporting on security lapses at the Secret Service, including the “Vegas bachelor party” in South America, and was part of the Washington Post team that scored a Pulitzer for its work on Edward Snowden’s war on the National Security Agency.

She also worked with Philip Rucker on A Very Stable Genius, one of the better and more informative books on Donald Trump’s time in the White House. Now she delivers her first solo work, Zero Fail. It paints an alarming portrait of those dedicated to protecting the president and offers a comprehensive look at an agency that has seen better days.

In 2009, Michaele and Tareq Salahi slipped through White House security, attended a state dinner and met Barack Obama. In 2015, a pair of soused senior agents crashed an official car into the White House complex.

There are incidents of shots being fired into the White House, an intruder making it into the building and an agent on Mike Pence’s detail hooking up with a hooker.

The Secret Service’s motto? “Worthy of Trust and Confidence.”

Leonnig tells of agents taking selfies with Donald Trump’s sleeping grandson. Trump asked their supervisor, “These guys weren’t being pervs, right?”

The response: “They were just being idiots.”

Zero Fail convincingly argues that the men and women who guard the president, the vice-president and their families are overworked. Leonnig also contends the Secret Service is a victim of mission creep, a buddy system saddled with out-of-date technology, a culture wedded to doing things because that is how they have always been done.

When one young agent brought a pair of fresh eyes to the situation, he was dropped. His critique is now the stuff of in-house legend.

Once part of the US Treasury, the Secret Service is presently housed within the Department of Homeland Security – a change that ultimately made little difference. Being swallowed by a bureaucratic Frankenstein did not help morale. The Secret Service became another body-part stitched to a cabinet ministry cobbled together in the aftermath of 9/11.

A boost to the budget was not sustained. Trump’s persistent travels to Mar-a-Lago left the Secret Service operating on a shoestring.

“Trump has set back this agency 10 years,” one former agent who departed during Trump’s tenure confides to Leonnig. “The overall culture and way of doing things took a big step back.”

Time has dulled the images of selflessness displayed in Dallas in November 1963 and outside the Capitol Hilton in 1981. Clint Hill threw himself on to President Kennedy’s limousine. Rufus Youngblood Jr used his body to shield Lyndon Johnson. Tim McCarthy took a bullet meant for Ronald Reagan. Jerry Parr bundled the president away.

Unwelcome occurrences are not always gamed out. As former agent Jonathan Wackrow puts it: “The policies and procedures of the Secret Service are born out of blood.”

When the planes slammed into the World Trade Center, agents removed Dick Cheney from his office but were delayed in delivering the vice-president to a secure location. Chains of command stymied his immediate entry into a designated shelter. That and the lack of a key.

In chronicling the heroics, failures and foibles of the Secret Service, Leonnig also opens a window on the families the agents served. Not surprisingly, some fare better than others. The Clintons and Carters trail the Bushes and Reagans.

White House Press Secretary James Brady and police officer Thomas Delahanty lie wounded outside the Washington Hilton after the assassination attempt on Ronald Reagan on 30 March 1981.
White House press secretary, James Brady, and police officer Thomas Delahanty lie wounded outside the Washington Hilton after the assassination attempt on Ronald Reagan on 30 March 1981. Photograph: The Ronald Reagan Presidential L/AFP/Getty Images

The agents respected and admired George and Barbara Bush. The feeling was mutual. The Bushes “treated the Secret Service agents who protected them and their large brood like part of the extended family – not like ‘the help’.” At Christmas, the Bushes delayed their celebration so agents could be home with their families. The former head of the Bush detail told Leonnig: “That’s why people would do anything for the President and Mrs Bush.”

The Clintons stood on the other end of the spectrum. Bill’s priapic adventures were a headache and Hillary came to be loathed. As for Chelsea, Leonnig tells of her cutting short a telephone conversation with a friend as agents arrived.

“I’ve got to go,” the youngest Clinton is remembered saying. “The pigs are here.”

Reminded that the agents’ job was to “stand between you, your family and a bullet”, Chelsea reportedly responded: “Well, that’s what my mother and father call you.”

The story spread. Suffice to say, Hillary’s “foul mouth” didn’t help her standing with those who protected her. Nor for that matter did the Secret Service’s personnel and culture, which leaned conservative and Republican. Bill and Hillary were children of the 60s. Military service and baking cookies were not for them.

Whether and how the Secret Service rebounds remains to be seen. In the aftermath of the insurrection of 6 January, “one Secret Service officer called the armed protesters ‘patriots’ seeking to undo an illegitimate election”, according to Zero Fail. The agent also “falsely claimed to her friends that disguised antifa members had started the violence”, a view still held by the former president’s minions. Members of the Trump detail have been reassigned.

To rejuvenate the Secret Service, work needs to be done. At a minimum, Leonnig’s book will get people talking and thinking.