Carrying a firearm aboard is a very personal choice, and one that must be made individually. I would never condem someone for choosing not to. The many reasons stated make that an appropriate decision for them. I do choose to arm my self. But, I have the training, the experience and the mindset to make that an appropriate decision for me and my family. The most dangerous weapon aboard is the one you aren't prepared to use. With appropriate training and research into the rules and regulations of your area of operation addressed, a firearm is just another tool, no more or less than any other tool in your inventory.
Just my two cents.