It's been 15+ years since Britain last had a mass shooting of any note (Cumbria) and nearly 30 years since a school shooting (Dunblane), in case anyone was wondering.
And both of those were far too little time ago.
(An observation: I can remember pretty much every shooting incident in Britain that's made it onto the news in my decades-long life. I can't even remember how many there've been in the past year in the US because they've all become a blur).