I was in Midtown Manhattan on 9/11 and when we finally realized what had happened and left our offices into the chaos of New York City, I eventually made my way to a pizzeria. With the little money that I had on me, I bought something to eat. It dawned on me that with the exits from Manhattan closed, I really had no place to go at that time. I asked the owner of the pizzeria whether he minded if he I stayed in the store for a few hours and learned from a sefer that I had with me. He answered, "That’s what we need!" So I sat there and learned for a while and then made my way uptown to Yeshiva University.
In the end, what other response can there be to tragedy of any magnitude than to pray, to study and to perform mitzvos?