The Sept. 11, 2001, terrorist attacks in New York, Washington and Pennsylvania opened a floodgate of both tragedy and security flaws in our nation.

We recently asked our readers to weigh in on whether they feel safer as our nation approaches the 16th anniversary of the attacks.

Have upgrades in security procedures at airports and other public places made a difference? Have other threats taken the place of the group behind the Sept. 11 terrorists as prime threats to our nation and its allies?

Today, we offer letters to the editor from Times readers who wrote in regarding whether they feel safer 16 years after the attacks that both redefined American resolve and how we view national and personal security.