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Twenty years have passed, but the memories of that morning are still so clear. I stepped outside for half a minute at about 9 a.m. on Sept. 11, 2001. It was a beautiful morning in New York City. It was a sunny, warm late summer day, and primary elections were just getting started.

I had been back in the military only about a year. I was an adult student at Hunter College on the Upper East Side and had joined the National Guard after a break in service from active duty to help pay for tuition. That Tuesday, after a morning swim, I sat down early for a 9 a.m. class. It was just a typical day.

Moments later, fire engines, sirens screaming, charged down Lexington Avenue outside the window. The professor couldn’t make herself heard over what seemed like the entire FDNY. After a few minutes a young woman in the rear of the class looked up from her cellphone and said:

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"An airplane just hit the World Trade Center." And in that moment, the world changed.

I rushed to the National Guard Armory down Lexington at 25th Street. Soldiers accumulated there all day. We weren’t sure yet what was happening, but we knew that’s where we needed to be. We spent time organizing and waiting for orders. It was all so frustrating. When night fell, we deployed as a unit to lower Manhattan and were assigned to secure the area from pedestrian traffic.

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I got my first look at Ground Zero that night. It was horrific, a war zone in my hometown. I ended up spending two weeks there, securing the site by night, directing traffic and catching a few winks by day.

Over the years I came to feel extraordinarily lucky. I knew what to do and where to go that day. I had a mission and a purpose. 

In the aftermath of 9/11, America had a mission and a purpose, too, one that I shared and actively participated in. While active-duty components of the military prosecuted a war against al Qaeda and their Taliban hosts, the National Guard worked to help secure the homeland. I spent time guarding the terminals at JFK airport between semesters.

I also participated as our mission strayed. I went to Iraq in 2004, where I proudly pursued justice against Saddam Hussein, without questioning the wisdom of the war. I spent most of 2008 in Afghanistan, long after the mission there turned from our initial goal of retribution to nation building.

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With experience comes wisdom, and my experiences fighting and watching our wars in the Middle East has changed how I see U.S. involvement in other countries.

With experience comes wisdom, and my experiences fighting and watching our wars in the Middle East has changed how I see U.S. involvement in other countries. As we confront the disastrous results of a series of bad decisions in Afghanistan, I know the wise approach is different foreign policy for our future.

Twenty years ago, America owed itself and the 9/11 perpetrators a reckoning. That fight was justified. Today we owe ourselves a foreign policy that deters aggression against America’s core interests and secures the conditions of our prosperity. A foreign policy that recognizes reshaping the world in our image, or even rebuilding a single nation to our liking, is not in our interests here at home.

I see the last 20 years as a whole now, from Ground Zero, to the mountains of Afghanistan, to watching the evacuation unfold on TV. 

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With this full picture, I have hopes for the future. Hope that our country will finally abandon nation building. Hope that we’ll consider the lessons of Vietnam, Afghanistan, Iraq, Libya and Syria the next time our leaders propose regime change efforts. Hope that future Congresses will only commit American lives to war when necessary to defend our core national interest. 

And finally, hope for accountability for those who have perpetrated decades of war against all reason at the expense of my brothers and sisters in uniform. 

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