It's easier to make libel charges stick in the UK. So guess what people do all over the world when they have high-priced lawyers and something to hide, and people who want to get the truth out on their tails? They drag you into court in the U.K. and sue you for libel there. It's called libel tourism, and it's often an effective method to silence people who don't have the same resources. It boils down to a form of specific censorship.
Make your voice heard to sign the libel reform petition here.