Is 4chan the perfect Pirate Bay poster child to justify wider UK site-blocking?

It's pretty straight forward, using its dominance when it comes to internet platforms to try to impose American speech standards and values on foreign countries, the vice president has been quite explicit about that when he interfered in political discourse in several European countries.

Any country that has its wits together would do well to establish sovereignty over its communications infrastructure. It's quite telling that the only country that has been able to stand up to American bullying is China because they were smart enough to not outsource control over their information space to the US.

...What? So given the option between the government having more or less control over what you can say, you'd prefer more?

Yes. We're not living in the world of some naive 90s internet libertarianism. If a country wants to maintain its sovereignty people need to collectively control their own infrastructure and have a state capable of doing so, unless you want to end up as a colony of US companies and the state department.

LOL. You're not talking about sovereignty (which would be the control of a state over its resources), you're talking about control of the populace. I'm perfectly fine with foreign businesses disrupting any state's ability to maintain control of its citizens. The more the better, as I see it.