I Common sense is wrong more than it's right. It's only good for making guesses about things you don't understand, and is worthless for evaluating things you understand.
You either don't understand what common sense is, or perhaps possess little of it yourself then. It's related to basic, common experience based judgement. I've known people who were math whizzes but had no common sense, and did really bone-headed things in regular life. Without a book or instructions to tell them how to proceed, they seemed a bit helpless, like a musician who can sight read perfectly but can't improvise a few measures.
AQ and ISIS have sites for their fellow jihadis-in-arms, there are definitely targets anonymous could choose to attack, but I won't hold my breath that they'll actually conduct the attacks they promised.
Australia belongs to...
. . . the largest concentration of deadly, poisonous critters and creepy-crawlies on the planet.
And then there's all the marsupials, snakes, and spiders