Not really for the UK, there's only 3 nuclear states entirely within range of our missiles and they're all close allies. One further nuclear state is partially in reach, Russia, but the UKs stockpile would be incapable of overwhelming Russian defences and isn't a threat to them. Obviously, NATO has a policy of "nuke-sharing" so there's still a viable "deterrent" for all NATO countries, but actually possessing our own nukes is just an international policy penis waving thing, and it's becoming increasingly unclear who we're deterring against, given all nuclear states are either close allies or major partners in business.
Still, it's a great excuse to get politicians to throw more money at inadvertently developing fusion tech.