My mother used to leave the front door unlocked. She used to leave the side and back doors unlocked, too. This was mostly a function of sloppiness - she had four kids, three pets and a whole lot else on her mind . but when pressed about it, she reasoned that anyone bent on intrusion would find a way and that it was all a matter of chance in the end.

She missed her calling as the director of the Secret Service.

What we’ve discovered over the last week and a half about the crackerjack operations of this elite agency boggles the mind, and nothing I learned during Tuesday’s congressional hearing into its procedures did anything to un-boggle it.

The subject was how, on Sept. 19, a deranged man managed to get deep inside the White House . much deeper, it turns out, than the agency initially let on. We were first given the impression that he’d merely made it through the front door. Only later did The Washington Post and other news organizations unearth that he had zipped down the vestibule, past a staircase, through the East Room and almost to the Green Room. By the time all the facts emerge, we’ll find out that he treated himself to a grilled cheese and a glass of Ovaltine in the kitchen, where he was interrupted mid-sandwich and given a doggie bag.

At the hearing, there were acute questions and ludicrous ones, genuine concern and disingenuous grandstanding, florid preening and runaway egos, which is to say that many politicians were crowded into one room.

There was verbiage so oblique it barely qualified as English, which is to say that government officials testified. Front and center was the head of the Secret Service, Julia Pierson, who behaved in the manner of so many beleaguered bureaucrats before her. She pledged reviews, reports, inquiries and assessments . a brimming thesaurus of self-examination . and tried to run out the clock.

She muttered sentences like this: “In downtown areas, there is sound attenuation.” This was a reference to the Secret Service’s confusion in 2011 over whether someone had been shooting at the White House or a motor vehicle in its vicinity had backfired.

The answer was shooting: Seven bullets hit one of this country’s defining symbols, which is also the president’s private residence, in which he and his family must feel . and be . unconditionally safe. And it wasn’t Secret Service agents who identified the evidence. It was a housekeeper, happening upon shattered glass days after the fact.

These aren’t minor, random smudges on the record of the Secret Service, which was also embarrassed a few years ago when agents on assignment in Colombia partied with prostitutes. They’re cause for grave worry and a different kind of housecleaning.

Nothing about the events of Sept. 19 honors the responsibilities and capabilities of a great nation. According to Pierson’s testimony, two agents that day had eyes on the intruder, who was known to them as a potential troublemaker and had shown up at the White House fence less than a month earlier with a hatchet. They were right not to detain him then: He’d committed no crime. But how could their monitoring of him during his return visit be so lax that he even got over that fence?

Not a beast or a beep worked properly. The guard dogs didn’t guard. The alarm boxes didn’t alarm. The front door couldn’t be locked automatically as he sprinted toward it, because it wasn’t rigged that way. We can fly drones over Pakistan, but we can’t summon a proper locksmith to 1600 Pennsylvania Avenue?

Time and again, Washington validates the naysayers who like to dismiss it as the capital of bureaucratic incompetence. The president unveils his signature health care reform . arguably the cornerstone of his legacy . and the website repeatedly crashes. The I.R.S. loses whole years of emails. A contractor for the National Security Agency steals away with a seemingly bottomless trove of classified documents.

The Department of Homeland Security fails to keep track of more than 6,000 foreigners in the country on student visas, or so ABC News reported in early September. And don’t even get me started on the Department of Veterans Affairs.

There’s precedent, yes, for White House intrusions. An uninvited guest once watched a movie with Franklin Delano Roosevelt before being detected.

And America isn’t alone. In 1982, Queen Elizabeth II awoke in Buckingham Palace to encounter a strange man in her bedroom. He and she reportedly chatted for 10 minutes.

I guess the palace didn’t have all the “layers” and “rings” of security repeatedly mentioned at the congressional hearing, though a lot of good all those layers and rings did us. In the end, it’s people who make the difference. The Secret Service needs better ones.