Getting a gasoline tanker close enough to cause sufficient damage (i.e.: inside) would be hard; not only does it have to get close, it has to get inside. WTC fa

Getting a gasoline tanker close enough to cause sufficient damage (i.e.: inside) would be hard; not only does it have to get close, it has to get inside. WTC famously had "10,000 pound planters" positioned around the buildings to stop vehicles from getting too close, and IIRC rather aggressive security preventing unwanted vehicles entering; they learned from the garage bombing about a decade before (just didn't extend vertically). Hijacking a just-took-off airliner was the most efficient & surprising way to transport & insert the liquids. Cockpit doors are a cheap sensible solution. 10,000 pound planters worked until somebody figured out how to go over them.