Video: Liam Fox: Liberal Democrats' Trident downgrade 'very, very dangerous' Proposals by the Liberal Democrats to downgrade Britain's Trident nuclear deterrent are "very, very dangerous" and represent "political posturing at its worst," according to former defence secretary Dr Liam Fox. The Liberal Democrats are expected to suggest that the Trident-armed nuclear submarine fleet be cut from four vessels to two, and the abandonment of the round-the-clock submarine patrols that have been conducted since the 1960s. Dr Fox, who is tipped for a possible return to the Cabinet after his resignation in 2011 over the Adam Werrity affair, said the plans were "not done out of any idea of principle, but simply to try to get votes at a general election, and that is not any party I would trust with my national security." "When you ask any former prime minister in this country, or a former defence secretary who has actually had to look in the cold light of the facts about nuclear deterrence, they will almost all of them tell you that a continuous at-sea deterrent is the most effective and practical way for Britain to protect itself from nuclear blackmail," he said.