'New Yorkers are not intimidated': Residents determined to move on after Manhattan explosion

New York is a target and New Yorkers know it.

Dave Cullen knew it when he moved to New York six years ago.

"Most people, especially in Manhattan, are here by choice, we all came here from little towns, all across America," said the author of Columbine.

"We've already weighed a version of this issue in our head and made the choice," he said. "I think for the most part people just shrug it off and go on with their lives."

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On Saturday night he found himself visiting friends when the explosion hit just four blocks away.

As news of the bombing emerged, they headed to the rooftop of their building, but instead of finding panicked residents, he found a scene that typifies New Yorkers' attitudes.

"Lots of other groups were up there and they were having drinks. And everyone's curious, looking over the roof, but then they sat down and just went on with their dinner parties" he said.

Curiosity and concern, he says, then turned to puzzlement.

WARNING: graphic images - 'Everybody was disoriented, running around': NYC bomb witness

8 years ago

Duration 6:39

Ramon Lopez helped the injured after a bomb exploded in Manhattan's Chelsea neighbourhood

"Why would they hit Chelsea? It seems like an odd place," he said.

The fact no one was killed, and the 29 injured were all released from hospital Sunday, may have contributed to the relaxed attitude for some towards the bombing, but there's something deeper.

'New Yorkers are not intimidated,' says mayor

Perhaps it's that reminders of the threat New York faces are so commonplace they've become routine. Thousands of commuters hustle past heavily armed National Guard soldiers in Grand Central Station every morning. In Times Square, amongst the selfie-taking tourists, are rifle-carrying members of the Critical Response Command, the special counterterrorism force created in the wake of the Charlie Hebdo attack in France.

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It's become a natural reflex for the city to increase security when attacks happen overseas. A city that's always aware the next Bataclan could be on Broadway. NYPD detectives are routinely dispatched to other cities in the wake of terrorist attacks.The NYPD claims 20 terrorism plots have been foiled in the city in the last two years alone.

"New Yorkers are not intimidated, we will go about our business," said Mayor Bill de Blasio on Sunday.

He told the story of one woman he met while touring the area near the explosion.

"One woman came in from Queens to go to a church nearby, I said 'Did you hesitate?', she said no. She said for one thing, God is with me and as for another thing, as a New Yorker I am going to keep going."

Terrorism is both a scar and a badge of honour in New York. Fifteen years after 9/11, New Yorkers remember where they were when the planes hit, or know someone who was killed or lost a relative. They also take pride in their ability to recover, rebuild and show resiliency.

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So when the Mayor announces a "bigger than ever" police presence after Sunday's bombing, on top of already stepped up efforts to protect world leaders in town for the United Nations General Assembly, it's likely to be met with equal parts relief, and equal parts annoyance for the added traffic and road closures.

Cullen thinks New Yorkers also take comfort in the numbers game, that in a city of more than eight million, with a few million tourists thrown in, the odds of being the victim of an attack are small.

That thought was on Cullen's mind as he rode a bike share home from Chelsea on Saturday after the explosion.

"I am much more likely to die getting hit on this bike."