Trident

The major issue of debate! Strange then that a very straightforward point escapes so many commentators.

The cost (which we'll not get into debating) comes out of the defence budget. Now, all our major parties are committed to spending 2% of GDP on defence, as it's a NATO edict. Clearly, if we didn't spend the money on Trident we could spend it on helicopters or ships, but what cancelling Trident won't do is free up a single penny for hospitals or schools. Unless you renege on that NATO commitment of course.

And here's another point, seeing you started it. Y'see, proponents are understandably as keen to downplay the cost (£31Bn) as opponents are to inflate it (£160Bn). Here's a question for Nicola who likes the convenient round £100Bn pricetag - if it was £100,000, would you drop your objection? No she wouldn't. It's not actually about the money.
It's morality.
Strange then that we'll happily go along with the NATO first strike strategy and joint exercises with nuclear armed forces.
Maybe it's not about morality either. Perhaps it's just the same old playing to the gallery for votes. Still, that's democracy.