We lost customers, friends and family on 9/11.

Our postal facility is directly across the street from the World Trade Center site. It is a constant reminder to us of what happened.

Images of the attack are embedded in my memory. Most devastating to me was witnessing people who joined hands and jumped from above the 83rd floor. I stood there feeling hopeless and confused.

Now, I am the carrier who delivers mail to 7 WTC, which opened in May 2006. Some days I feel like I will not let hatred keep me from my appointed rounds. I have added to the postal motto: Not rain, snow, heat or terrorism can stop me from delivering the mail. Yet, there are those days when I ask: Why?

Clark is a letter carrier at the U.S. Postal Service’s Church Street Station in New York.