The London "Unite the Kingdom" Rally

 Even the 9/14/25 Guardian admits it was big:

Between 110,000 and 150,000 were estimated by police to have attended the event. The Met said in an update on Sunday that there were 24 arrests, including for common assault, actual bodily harm, affray and criminal damage.

That many arrests in a crowd of 150,000 people is not terribly high.  That someone got the message shows:

The business secretary, Peter Kyle, said the number of people who turned out for the “Unite the Kingdom” protest – organised by the far-right activist Tommy Robinson – shows free speech is “alive and well” in the UK.

Kyle added that moments like Saturday’s demonstration were “klaxon calls to us in public life to redouble our efforts to address the big concerns that people right across our country have, and immigration is a big concern.”

That is 0.2% of the United Kingdom's population.  If you think that is not much, remember that to get into notoriously congested London is not a trivial undertaking.  That would be equivalent to 660,000 Americans going to DC.  The only question is whether Labour will do anything or just look for more ways to suppress dissent.