Not a terribly convincing government papper from Blair and his mates in 2006. It raised a lot of questions in my mind. Just a couple for now.
The big elephant is the statement made in 06 that it would take 17 years to field and the extant system would be out of service in the early 2020s. Why didn't they do anything about it then before it was too late - especially considering the statement that life extensions were unlikely to be effective or for particularly long. We now have fewer that 10 years to decide upon a system and get it into service.
The whole thing was clearly written to support only one option and to discount the others on cost and effectiveness grounds. SSBN is the obvious answer, but the other choices cited were so obviously flawed. The air option, for example, was 20 airliners carrying nukes, with the attached claim that they're easy to shoot down. Really?
Whilst they include the costs of building bases for the air option, they have omitted to include the cost of emptying, cleaning and then rebuilding Faslane and Coleport. Oops.
Way to much political spin in there to be convincing.