Admittedly, Trident has really only one function: MAD. But that suffices to protect us from nuclear blackmail. You can have as many other nuclear ideas as you can afford after that.
Agreed, but we need to maintain that capability, no matter how much the wicked witch of the north and her party berate it.
The Ukraine shows what can happen if you give up your capability, no way would Russia have ever marched into the Ukraine had it remained, but they gambled that we the west wouldn't back up our promises with conventional forces, and sadly we proved them right.
All that ensured was that no Country with capability will ever renounce their nuclear weapons again.