The butterfly effect purports that the flutter of a butterfly's wings could ripple like a chain reaction that eventually creates outsized, widespread change -- such as a tsunami battering a shore thousands of miles away.
The concept is instructive when trying to grasp the effects of what happened on a sun-kissed September morning in 2001. In many ways, those effects are just now coming into focus.
For students at Stuyvesant High School, three blocks away from Ground Zero in New York City, September 11, 2001 played out like a scene they didn't want to be a part of. The day was so beautiful. The memories will be with them forever. And their lives were inexorably changed by the flutter of fate's wings.
Juan Angel Arce, sophomore on 9/11, currently works as a political officer for the United Nations Secretariat:
"At this point it's a little bit difficult, saying what I saw. There is the iconic Spectator cover [Stuyvesant's school paper] which feels like a memory. I remember walking up the west side highway and turning around every couple of blocks. Just a state of shock that this was happening at all. Confusion, lack of understanding. So unlike anything we would expect. At 14, 15 -- it's an age when people are not politically aware. It's surprising how much the passage of time can change one's recollections. The more we hear about other's recollections, documentaries and reporting. It's almost like a shared universal experience of September 11th."
Stuyvesant High School is a specialized high school, one of the most competitive in the city. Many of its graduates go on to top universities and a wide array of successful careers. But on 9/11, they were just teenagers, still out to find themselves and their way towards adulthood.
Arce, half-French and half-Mexican, is careful when trying to characterize how 9/11 affected his life and his career path.
"Being the son of a diplomat [his mother Angelica Arce is a career diplomat from Mexico], I always felt an interest in international affairs," he says.
"I don't know if I went into international relations because of 9/11 but it was a really important factor."
And what 9/11 did do, he is sure, was infuse him with a need to understand how things could get this far.
"Part of me wanted to figure out how people could be so different, that something like this could happen," he says. "How people could be driven to such extremes that they would see each other as targets?"
"Warning bells rang," Arce says. "If people don't take the time to try to understand each other, [and learn] what could motivate others to do inhuman, terrible things like this, then September 11th won't be a one time event."
For college, Arce went to Georgetown University where he majored in international affairs. Eventually, he chose to learn Arabic.
"Working in international diplomacy, its important to understand people," he says.
"Syria, for example; If you meet with some of the better off people who learned English, French, you get one exposure to a cross section of the people. But speaking Arabic you are able to talk to the poor people. It's very disarming to the people. That you took the time and the effort to learn a very complicated language," he adds.
Arce works for the United Nations Secretariat as a political analyst. His department analyzes what is going on in the world politically, economically and socially.
"The UN is the only organization in the world that brings people together to discuss issues that may be threats to international peace and security," he says.
Madeline Martinez, sophomore on 9/11, pursuing Masters in International Policy and Development from Georgetown University:
"It was just a feeling of shock. Being from Latin America, growing up with family in Peru and Colombia, violence happened there. But this was the first time you were seeing people with heavy artillery enforcing security in New York. It was the understanding that we weren't necessarily invulnerable anymore...I just remember a general sense of unity as a sophomore. It was a new experience to be down in Manhattan, connecting with students. Afterwards we were not necessarily best friends but we always had that day."
Martinez, was 15 at the time, just like Arce. And a bond she forged on September 11, 2001 stayed with her throughout high school.
"I was one of the people that was visibly upset while it went on," she says. "I was on the tenth floor. I saw the towers collapse and I thought we were in trouble. Then we evacuated and I realized we would get out ok. The first person I met up with was a friend, Edward Boronowski. I dated him from that day forward and all throughout high school. It really was a romance born out of a tragedy."
As Martinez turned her attention to college and thoughts about her path in life, she found herself drawn to the idea of improving the United States' image in the world.
"My interest in foreign policy originated after September 11th," she says. "Simply, because I thought we could see the mistakes repeating themselves: We were just jumping into a very subjective, premature, aggressive action [in Iraq].
"I want to work in preventative diplomacy," Martinez says.
"In that I'm looking to improve the relationship the U.S. has with trading partners, specifically in Latin American countries. By building stronger ties, the GDP will improve, which will lead to a more secure hemisphere and a more secure geopolitical dynamic," she added.
She is currently getting a Master's degree in public policy, which she describes as "a professional degree that gets people to understand how public revenue is used to impact social change."
Arthur Burkle, junior on 9/11, pursuing law degree from Fordham University.
"I was in Spanish class when we heard a boom but I thought it was construction. A girl came in crying saying that a plane had just hit the World Trade Center. I thought that was crazy but nothing to cry about. Another boom and a brief blackout, then we exited through the back door to the West Side highway. A cloud of dust was coming. It was very confusing. I saw the cloud but I didn't know the towers had fallen."
"Later I took the A train home. I lived in Rockaway [in Queens] at the time. Part of the train ride goes above ground and skirts Jamaica bay. JFK [airport] was on one side and a cloud of jet black smoke was on the city side. My understanding is that a lot of the firefighters lived in Rockaway. The community was devastated. I didn't know the magnitude then. But we still feel the shockwave today."
Burkle is Mexican with German and Polish roots. As he prepares to graduate from Fordham University with a law degree, he says that 9/11 didn't lead him to work in immigration and then to pursue law. But he remembers that it set off a chain of events he wasn't happy about.
"It led to the war In Iraq, they used [9/11] as an excuse, which made me pretty cynical," he said.
"I was pretty sad not to have the Twin Towers. We used to hang out there. In the ensuing years when they couldn't decide what to build and there were money problems -- that made me more cynical."
A Legacy of Unity
Each of the students recalled how everyone came together in the wake of 9/11.
"One of these images that I'll never forget is people trying to go to Ground Zero, to go donate blood," Arce said. "Willing to do that and being turned away. Not knowing how to help but feeling that they had to do something."
"What touched me and my parents the most was that, in the aftermath, the entire New York City community came together," he continued. "Humans reaching out to humans. Helping out in their neighborhood to do the right thing."
"It was a human reaction, to suffering, to the unexpected. An act of solidarity."
Contact Adrian Carrasquillo at Adrian.Carrasquillo@foxnewslatino.com or on Twitter @RealAdrianC.
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