Cameron's warning of a Chinese threat is illustrative of a cold war mentality that fails to recognize the vast disparity in power.
The Conservative leader David Cameron insisted last week that Britain must spend almost £100bn to maintain its independent nuclear deterrent as "we don't know what is going to happen with Iran [and] we can't be certain of the future in China".
The foreign secretary, David Miliband, described the comment as showing "appalling immaturity". The Conservatives issued a statement claiming that Cameron was "demonstrating the extent of uncertainties in the world, not saying China is a threat to the UK". Yet the Conservative party's manifesto shows a somewhat contradictory position on China, urging "closer engagement" while "standing firm on human rights" and stopping aid.
The management of Britain's armed forces and the future of defence spending may dominate the agenda when the three main party leaders meet for this week's TV election debate.
Writing on British foreign policy choices in this month's issue of The World Today, Christopher Hill complained that "for too long we have muddled through with inherited notions of indispensability and grandiosity". It is perhaps this grandiosity that prompted Cameron to warn of the Chinese threat.
The reality is that Cameron forgot who the superpower is. There is vast disparity in power that cannot realistically be glossed over by banal rhetoric. Britain's population is 4% that of China's, and has armed forces of just over 240,000 compared with the vast Chinese People's Liberation Army of over 3.4 million. Crucially, courting China will play a key role in dealing with the pressing Iranian nuclear issue. China is Iran's biggest export partner, and sells it back refined oil. Time magazine urged Barack Obama this month to "replace US outdated ideas for dealing with China" and "to move beyond cold war containment".
Among the key questions are whether it is Britain's independent nuclear deterrent that keeps it at the top table of foreign relations, whether a war-weary population actually wants to be at this table any longer, and whether the country can actually afford to keep punching above its weight - especially considering that the Ministry of Defence will be facing a £6bn shortfall by 2020.
First, a reminder that Britain's nuclear deterrent is not as independent as some would think. As Dan Plesch from the Centre for International Studies and Diplomacy has shown, the Trident system is almost totally reliant on American technological knowhow and components, including its "computer software programs, the fuse, the trigger, the guidance system as well as the missiles".
To focus on Cameron's point: in a post-cold-war world can a (semi) independent deterrent determine British-Chinese relations? Having nuclear weapons may have given Britain a permanent seat on the UN security council, but that institution has been proved to have only limited scope in resolving the issues of the day. Britain's role in bilateral (US) and multilateral (Europe, Nato) ties and trade and cultural relations are surely far more important. Co-operation on the green agenda does not and cannot come at the end of a nuclear warhead, yet politicians who fear that getting rid of Trident would alienate a portion of middle England used to a diet of free Daily Mail DVDs about the second world war and brought up on nostalgia for the indispensability that Christopher Hill describes. I remember attending a recent Conservative party conference where a disproportionate amount of time was spent complaining that Britain's Royal Navy is no longer as large as that of the French.
Cameron's unscripted comments described the dangers of today's "uncertain world", as if the hair-trigger from nuclear Armageddon that characterised cold war stability was somehow a blessing. Obama's recent conference on nuclear terrorism and the landmark agreement with the Russians shows that significant advances can be made on global disarmament.