Whoops apocalypse, not!
So an unarmed Trident missile took a wrong turn towards the USA, not the sea near Africa.
The UK media are pressuring the government to give our enemies insight into our primary deterrent.
Of course, it is very political, no one realising that all complex technical systems, including Space-X rockets, will sometimes fail.
When it comes to a real nuclear exchange, failures like this, that are tests, will have ironed out most if not all the serious bugs. If we let our enemies know of any flaws in new systems, then it leaves us with our shields down, so it needs to be covered up.
If there is an accident and people are killed or injured, then that is a different thing.