Worldcon is easily accessible and the Worldcon is a BIG Name event… and if you think that an event that features so many writers and media people with an International profile isn’t a BIG event in the UK then I humbly submit to you that you are wrong.As I pointed out to him, the Worldcon, while important within our community, isn't even important enough to the UK publishing industry, let alone anywhere else. In 2005, we couldn't get the publishers to pay attention to the Glasgow Worldcon, despite the UK authors being nominated for Hugo Awards, because it was a minor event of little importance to them.
I simply find the idea laughable that a World Science Fiction Convention would be a significantly important target compared to high-profile sporting event or political conference. If the terrorists start targeting as low as us, then long before then the entire world will have shut down because you won't be able to step outside your door without setting off the bomb on your doorstep.