If it helps, there's no hard and fast rules...
It's just that some pictures put people off a lot more than others - this one in particular causes a bit of discomfort, whereas other things such as the twin towers are more of an abstract concept, thus more tolerated (though not completely). That said, there are certain WTC pictures that are also not guaranteed a welcome on here...
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Thu 21 Aug 2008, 17:24,
archived)