My older son was in second grade doing a bird report on the northern cardinal when it hit me: the absurdity of America’s security obsession.

We’d stepped through the front door of our neighborhood library on Capitol Hill when I heard the rip of the Velcro fasteners on his little-boy sneakers.

“What are you doing?” I asked, incredulous that he was taking his shoes off to go into the library.

He soberly pointed to the book-scanning device at the door that looked like the metal detectors at airports and museums.

“For security, Mom,” he responded, equally incredulous that I could be so blasé about such matters.

Thus has been America’s scanned and secured age, two decades in which forests of steel bollards sprouted around every possible target and we removed our shoes, belts and dignity in a frenzy as we tried to protect our nation from outside terrorists.

We got an especially heavy dose of that security theater here in D.C., as the entire city went into a rolling lockdown after the Sept. 11, 2001, attacks.

As a reporter who then covered federal lands and buildings in Washington, I listened for hours to some of the nation’s top architects and security experts debate this new era of American architecture — an architecture of fear, one that stifled sweeping plazas, open designs, historic preservation and the rhythm of city life.

Bollards — the basic kind of short, sturdy posts, each of which can cost thousands of dollars — are “the steel crabgrass” of Washington, architect and urbanism professor Witold Rybczynski told me in 2006, when he was a U.S. Commission of Fine Arts member debating the proliferation of security measures.

“We used to mock an earlier generation that peppered the U.S. capital with Civil War generals on horseback; now I wonder what future generations will make of our architectural legacy of crash-resistant walls and blast-proof glass,” Rybczynski wrote in a Foreign Policy essay on how bonkers D.C. had gone for security architecture.

And the fear wasn’t limited to the capital city.

Taxpayers from Thousand Oaks, Calif., to Memphis to New York City paid the bill for millions of dollars in bollards, scanners and cameras to protect people from terrorism.

D.C.’s U.S. Capitol complex planted a perimeter of 5.5 miles in bollards that could stop a truck from barreling into a building, most costing at least $7,000 each.

And yet, last week, it wasn’t ISIS, Boko Haram or Hezbollah. It wasn’t an organized militia or well-trained suicide bombers driving a truck who got into the Capitol building and left five dead.

It was a mob of Trump supporters who knocked down at least four security barriers, broke windows and beat police officers, an insurrection that left five people dead (a Capitol Police officer died of injuries he suffered during the riot).

The threat came from within.

While our leaders have occupied themselves with building barricades, while we took off our shoes and let airport security take ghostly nudies of us with high-tech cameras, we never thought people could be radicalized in our own neighborhoods and even in our homes.

And the power structure in Washington didn’t see them coming because it refused to believe the enemy could look like White America.

Their radicalization was right before our eyes, on social media and television, on bar stools and at our Thanksgiving tables, masquerading as politics and salty humor in memes, stickers and T-shirts. Or presidential messaging, such as President Trump’s “stand back and stand by” message to the white supremacist-tied alt-right Proud Boys group.

Our governments, from city councils to federal branches, built structures that they thought could prevent attacks — and they may have.

But putting all that energy into security that may thwart obvious threats ignores the ones that are in our blind spots.

We watched all those security measures in our seat of government trampled by fellow Americans — police officers, firefighters, business owners, veterans and even at least one elected leader.

The bollards and the metal detectors at every door didn’t stop them.

But acknowledging that we can be our own, most lethal enemies — that domestic terrorists kill more Americans than foreign terrorists — is crucial.

FBI Director Christopher A. Wray explained this just over a year ago in testimony before the House Homeland Security Committee.

“Trends may shift, but the underlying drivers for domestic violent extremism — such as perceptions of government or law enforcement overreach, sociopolitical conditions, racism, anti-Semitism, Islamophobia, and reactions to legislative actions — remain constant,” Wray said.

The people who easily bypassed the bollards and fences to terrorize the Capitol said they were there as patriots motivated by policy or politics or partisanship.

Baloney. They’ve been called terrorists — by members of both political parties, including President-elect Joe Biden. And unmasking them, treating them like terrorists, refusing to accept their threats or excuse their violence is more powerful than any bollard will ever be against their threat.

Twitter: @petulad

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