A report suggesting that moving the UK's nuclear deterrent out of Scotland would not be impossible raises questions about the location to which such a facility would be moved.
The move is not simply a case of finding another deep water location in a relatively low-populated area, but more about the infrastructure involved in running such a complex nuclear programme.
What is needed?
A deep water jetty - with sufficient room for multiple submarines and an undercover structure
A separate arming jetty - to securely take all missiles from storage to the submarine
A ship lift - to carry out emergency repairs
A large safe and secure weapons storage facility - with specially constructed explosion prevention systems
Excellent transport links - to transport weapons and other specialist equipment to and from the main storage centre in the south of England. This requires a major risk assessment
There are two sites where a facility of this kind could be set up, but both have their downfalls.
They are Devonport near Plymouth and Barrow-in-Furness in Cumbria.
According to independent nuclear engineer John Large, an overseas location, such as Gibraltar or Malta, could be considered.
He says America would be ruled out due to incompatible equipment.
He also outlines that servicing and moving weapons of this calibre makes the programme "vulnerable to sabotage and attack".
There are additional issues of moving several hundred members of staff and their families and the problem of radioactive waste from decommissioned weaponry.
The process of moving the Trident system would take up to 15 years.