Britain’s retreat from free speech has been going on for decades. But the pace of its state-backed muzzling of opinion has picked up in recent years. The radicalized centrists who constitute the U.K.’s establishment are panicking that online opinion is disrupting their narrative. This could be tricky, because that storyline — from the beneficial effects of mass immigration to the necessity of net-zero — is daily becoming more detached from anything that can be passed off as reality. Appallingly. Britain’s Tories, whether out of (past?) center-left sympathies or — and this still seems to apply under their latest leader — ...