Over the past three weeks, Austin watched in horror as a methodical madman detonated one shrapnel bomb after another in this seeming laid-back oasis. An unemployed 23-year-old loner killed two people and injured four others, before blowing himself up early the morning of March 21 as police closed in.

As an army of federal investigators packed up and left town, the city's quirky civic slogan, "Keep Austin Weird," took a blow.

The Austin bombings are further proof, to some observers, that this city of a million people — 2 million if you include the burgeoning five-county region — has grown up. Austin is now the nation's 11th-largest city, with its population up 20 percent since 2010. And no amount of tattooed guitar slingers, smoky barbecue joints, ice-cold swimming holes, offbeat art installations or creative food trucks will minimize that.

"This was a small town when I got here in 1972. I never locked my doors, for years," says Ray Benson, a civic booster and the 67-year-old founder of Grammy-award-winning country band Asleep at the Wheel. "But big cities come with big-city problems, one of them being serial-killer bombers."

Of course these days, communities of every size are targeted by active shooters, with terrifying regularity. But there is a palpable sense here in the once-mellow capital of Texas that its innocence is long past.

"There's a chance we may never be the same"

Austin has entered the major metropolis category in fits and starts. The city finally adopted a system of single-member city council districts in 2012. In the past two decades, while other big Texas cities expanded their freeway systems, Austin lagged behind and only recently got serious about adding lanes for the crush of commuters. And the city is finally upgrading its development code to increase urban density.

In 2014 the cocoon of coolness — the South By Southwest music festival — was burst when a drunken driver plowed into a late-night queue of music lovers, killing four people.

Now comes the Austin serial bomber.

"Random, senseless things happen that we can't understand," says Michael Miller, archivist for the City of Austin. "We want to control that. But the bigger we get, we can't."

Ken Herman, the sardonic columnist for the Austin American-Statesman, wrote after the bomber was killed that " there's a chance we may never be the same again." But he added, "There's an even better chance that we'll come out of it in better shape than many communities would. Austin's kind of weird that way."

Mass violence and racism

But even before Austin became a quirky boomtown, it had been forced to search for sense in maniacal violence. Austin has two dark distinctions.

In 1966, Charles Whitman ascended the University of Texas tower and murdered 14 people — the nation's first mass school shooting. And in 1884-85, the Austin Servant Girl Murders became one of the nation's first serial murders. The killer, never caught, attacked eight people asleep in their beds and finished them off with an ax.

The latter holds a disturbing contemporary parallel.

"When you look at news accounts in the white press, early on the city wasn't that scared because it was happening to black people," says the historian Miller. "When two white women were murdered on the same day, that's when you saw huge headlines in the Statesman."

This month, there has been criticism that police and media did not pay attention to the serial bomber when the first victims were black and Hispanic, only when an explosion in a well-off neighborhood injured two young white men. Law enforcement pushes back that it was the random nature of a trip-wire bomb that injured the white men that sounded a general alarm, and that the original bombings were widely covered in local media.

Black citizens also point out that Austin has not, historically, been as benign as its reputation suggests. In 1919 the secretary of the NAACP, a white Irishman named John Shillady, came to town on an anti-lynching campaign. A mob beat him nearly to death, put him on a northbound train, and told him not to get off to seek a doctor until he was out of Texas.

"We have a very complicated history, and because we don't explore it, we don't understand it," says Jeff Travillion, an African-American commissioner for surrounding Travis County.

Know thy neighbor

Austin remains a destination city, to be sure, and the bombing is unlikely to change that.

City leaders pointed out, in the midst of the bombing drama, that Austin has a low violent-crime rate compared with other major U.S. cities. Moreover, the highly educated population and local high-tech employment base — including Dell, Samsung and Google — make it a municipal superstar. And Austin consistently holds the No. 1 spot on Forbes' list of livable boomtowns.

But consider the bomber, Mark Conditt: He lived in a sleepy Austin suburb, and reportedly kept his murderous tendencies and his bomb-making room secret from his neighbors, his family and even his roommates.

"As a community, we do not know our neighbors as we should or perhaps the way that we used to," Mayor Steve Adler told a press conference Thursday night. "The legacy of this event for us should be that we walk across the street or the hall and introduce ourselves to our neighbors."

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