
The aim of terrorist groups is to kill as many enemy targets as possible, so any place with a high population density will make a more tempting target for them than low-density suburbs or rural areas.
OA-Cities will certainly be high on terrorism’s target list but, that said, their very compactness coupled with their controlled-access points – will make them very defensible and almost impossible to infiltrate compared with conventional OB-Cities which are so open to infiltration.
None of the terrorists’ favourite mass-killing methods would work against OA-Cities

- Motor vehicles will have no means of access, so truck/car bombs, etc, or using vehicles to run-over scores of people would be impossible to stage.
- A dual layer of airport-style security control – at the outer perimeter and then at the building entrance itself – will make it very difficult to smuggle in weapons or bomb-making materials.
- Any weapon or explosive device which did manage to evade these controls would be quite small and relatively ineffective in a large building.
- In a worst-case scenario where a hijacked plane manages to score a direct hit, a pyramidal building’s innate structural stability would prevent it collapsing catastrophically like a sky-scraper.

- Unlike closely packed sky-scrapers, OA-City modules will have a “clear field of fire” and, depending on future political conditions, they COULD be protected by radar-controlled “Phalanx” Gatling guns.