There is a big difference between a Cessna 172 with a gross weight of 2,450 including the 56 gallons of fuel and an A380 with a maximum takeoff weight of 1,268,000 pounds and 65,000 gallons of fuel.

Did you know the Twin Towers were actually designed to withstand a jet? https://archive.seattletimes.com/archive/19930227/1687698/tw...

Except they assumed that it'd be a 707 and also that'd be at landing speed of about 180mph ... not a 767 (which could be as much as 2x a 707 in take off weight) doing almost 600 mph.

A plane larger than a Cessna, but still no jumbo jet, crashed into a mall https://www.eastbaytimes.com/2010/12/21/the-sunvalley-mall-p... - 7 people died. Tragic, but it goes to show that SIZE DOES MATTER.

Also also. "no alarm bells" is highly dependent on location. If this "stolen" plane were to have flown into highly controlled airspace without approvals, you can bet your ass that alarm bells would have gone off. But the person flying the plane knew what they were doing and where they were going. They went away from busy areas and didn't anything out of the ordinary.

Is there still many reasons this could be a problem? Sure. But invoking the terrorism word is full FUD, the likes of which the media loves to use. And ends us with security theater like shampoo size limits.