By Gio Benitez and Angel Canales

We might think it's a natural instinct for people to run from danger. How do we explain, then, those people that run toward dangerous situations to help?

As a first responder, New York and New Jersey Port Authority Chief John Ryan has spent the last 35 years serving and protecting others, sometimes putting his life in danger. Ryan's biggest test was during the September 11 attacks. He spent nine months at the World Trade Center site in charge of that recovery operation.

ABC

From his office at the JFK Airport in Queens, N.Y., Ryan spoke to ABC News' Gio Benitez about the mindset of first responders.

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On first hearing of the Boston bombings, Ryan recalled, "My initial thoughts went out to the people injured, hurt and killed in the explosions, and then my mind re-focused on our response and preparation to deal with any potential incidents that might occur here. I had to make sure that all of our Port Authority police personal were alerted to what was occurring and also preparing themselves to be in place to respond and either deter, stop and react to the way they've been trained to."

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It's not just the training, though.

Ryan suggested that there may be some inherent quality in first responders, that makes them put aside their own safety to help others.

"I think beyond the career, it has to be something that has to be almost born into you. Courage is something that can't be taught…Nobody knows how they'll respond until an event happens and they are present," he added. "It has been my experience that the average American has that inherent desire to help other people and you see that time and time again."