The world we live in today is a dangerous, evil world. What happened there could happen anywhere. Disarming the citizens will not prevent that kind of attack and as most of us know only makes it more likely. Terrorists like the thugs and bullies they are would prefer a week, defenseless target.
"The great object is, that every man be armed. [...] Every one who is able may have a gun."
Patrick Henry
By faith Noah,being warned of God of things not seen as yet, moved with fear,prepared an ark to the saving of his house;by the which he condemned the world,and became heir of the righteousness which is by faith Heb.11:7