I lived in NYC close to the World Trade Center during September of 2001.
For me, the matter was settled during the 9/11 attack. I was on the communications team supporting the Red Cross in response to the aftermath where I witnessed firsthand, the necessity for hams to be a part of the communications system.
When the Twin Towers collapsed, the local cell phone infrastructure went with them. Mobile phones were useless for quite a while and landlines were overloaded--making calls in or out of the area nearly impossible. ALL of our public services (PD, Fire, EMS, etc.) were completely overwhelmed and focused on ground zero where firemen, cops, civilians., etc. where dying by the scores; jumping out windows to escape the inferno inside the building and crushed under fallen debris....chaos on the public service freqencies and those outside the city couldn't communicate with family members and friends scrambling from what had already happened...and what might happen next.
Ham radio was critical in the coordination of rescue and relief efforts. Operators halled car batteries on luggage carts, antennas stuck to anything metal (tables, chairs, bookcases, file cabinets) stationed at high school gyms, makeshift shelters, on ambulances, at ground zero, etc. We kept our cool, remained organized and efficiently assisted in any way we could--it worked flawlessly.
Something like that fatefull day on a warm, clear day in September will probably happen again. I'm ready and willing--even if I have just a wet noodle, my trusty Clegg HT with one crystal and a bag full of D cell batteries.