White House intruders. Sex and booze scandals. The worrying decline of the American Secret Service

Their mission can be perilous and delicate. They are expected to take a bullet for the President and keep him safe both at home and overseas. Loyalty and discretion are prerequisites as important as guts and courage. Thank goodness a few things these people do are more straightforward – such as securing the White House.

Hence the astonishment that even in that task agents of the US Secret Service were found lacking when late last Friday a man jumped the fence separating the executive mansion from Pennsylvania Avenue, dash unimpeded across the lawn to the North Portico and made it through the front door. (No one had thought to lock it.) It was the kind of mess-up that would prompt most of us to change our home security company without delay.

President Barack Obama, who, by the way, had left the White House with his family just minutes earlier for a weekend of rest at Camp David in Maryland, is not, of course, your usual homeowner and taking the contract to protect him away from the Secret Service is not really an option. Some would say that’s exactly what they deserve, however. This has had hardly been their only lapse since the Obamas took the keys to number 1600.

Recall the “Cartagena Prostitute Scandal” when 13 Secret Service members, dispatched to the Colombian coastal city in early 2012 to prepare for the arrival of Mr Obama a few days later for a regional summit, allegedly got carried away in a downtown club and later availed themselves of some of the finest in local professional sexual services in the privacy of their hotel rooms. Only three returned to work after a red-faced internal investigation.

Something also went awry when three Secret Service agents were sent home in disgrace from the Netherlands in March this year after a night of alleged drinking. One of the trio – all remain on administrative leave – was found passed out on a hotel hallway floor. And in May this year reports surfaced of agents – who were meant to be watching the perimeter of the White House – were assigned to keep an eye on a friend of the then director of the Secret Service who was being harassed by a neighbour. In Maryland.

The intruder on Friday was later identified as Omar Gonzalez, 42, a former soldier from Texas who has done tours in Iraq, and who is expected to face charges in a Washington court this morning. According to a lawyer who will defend him, Mr Gonzalez did it because he was worried “that the atmosphere was collapsing” in the country and needed to contact the President “so he could get word out to the people”.

Secret Service director Julia Pierson responded by pledging a review of all procedures at the White House which, until now, had been considered one of the most effectively protected installations in the world. The agency had suggested that no one had opened fire on Mr Gonzalez as he hurtled towards the President’s front door because he wasn’t armed. It subsequently emerged, however, that he was holding a small penknife with a serrated blade.

Mr Obama is bound to forgive the incident but clearly thought it serious enough to issue a statement of enduring faith on the agency. “The President has full confidence in the Secret Service and is grateful to the men and women who day in and day out protect himself, his family and the White House,” White House spokesman Frank Benenati said, adding that the President expected Ms Pierson’s review to be conducted “with the same professionalism and commitment to duty that we and the American people expect from the US Secret Service”.

It hardly helped that on Saturday another incident occurred when a man who had been turned away at a pedestrian entrance to the White House after demanding to get in then appeared several minutes later at a traffic entrance and refused to move his car when he was denied access again. The man was arrested.

Some in Washington’s political classes are less than impressed. Friday’s event was “absolutely inexcusable”, bellowed Peter King, a Republican congressman from Long Island, suggesting that the Secret Service could expect congressional hearings into the affair. “This demands a full investigation – an investigation as to what happened, why it happened and what’s being done to make sure it never happens again.”