Defence Secretary Michael Fallon watches as the first piece of steel for the next generation of nuclear submarines is cut in the plate production manufacturing facility at BAE Systems. Phil Noble/PA Images. All rights reserved.If a week is a long time in politics, then the six weeks since the general election in the United Kingdom on 8 June seem an eternity. The Westminster parliament's summer recess begins with Jeremy Corbyn’s Labour Party having transformed its electoral prospects and the Conservatives reduced to a chaotic state. Few could have imagined this outcome when the election was called on 18 April.

Such is the febrile state of British politics that it is impossible to predict how long the Conservative government will last and whether, if it does fall, Corbyn gets the chance to form a minority administration or whether another general election will be called.

Corbyn’s Labour Party has a serious chance of getting into power.

What is more certain is that Corbyn’s Labour Party has a serious chance of getting into power. If and when it does, it will have to deal with Brexit and all the complications that go with that. But Labour will also have to handle two key decisions already taken in another big policy area, that of defence and security. How the party prepares for this inheritance could be crucial to its chances of winning the next election, and to being successful in government (see "Corbyn's Labour: now look outwards", 16 June 2017).

The impact of the first decision became clearer in the launch of the Royal Navy’s huge new aircraft-carrier HMS Queen Elizabeth. It was commissioned in 2007, alongside its partner vessel the HMS Prince of Wales. The combined cost of these ships amounts to well over £6bn. At 65,000 tonnes, each is designed to have three times the displacement of the carriers they succeed. The second decision, confirmed in 2016, is the replacement of the UK's aging Trident-missile submarines with new boats, at a core cost of over £30bn.

The public might assume that for all the expense in replacing the Trident submarines and building two huge new aircraft-carriers, this still represents a small part of the overall defence budget. But this would ignore the huge resources needed to deliver these programmes. An aircraft-carrier does not operate on its own. It has to be at the centre of a whole flotilla of escorts (destroyers and frigates) as well as a nuclear-powered attack-submarine, auxiliary ships and maritime air-cover.

The same applies to a Trident submarine. Here the assumption is that such a submarine leaves its base and disappears into the depths only to emerge at the end of a patrol some months later. Again this is not the case, because of a little matter called “deterrence support”. This is likely to include a nuclear-powered attack-submarine, maritime air-support, and an escort or two readily available on call.

To all this, add in the fact that keeping a warship at sea and fully operational commonly requires three ships – to allow for passage, training, re-equipping, maintenance and regular refits.

Put bluntly, maintaining an aircraft-carrier of the size and complexity of HMS Queen Elizabeth and a Trident submarine will require a very large chunk of the whole Royal Navy. It will leave Britain with the capability to engage in expeditionary warfare and fight a nuclear war, but – at least in terms of global policy – not too much else (see "British sea power: a 21st-century question", 13 July 2006).

New generations, new policy 

The problem for Labour is that all this is already decided, whereas any sensible line of thinking would mean Britain giving up its pretence of being a global military power. It would cancel the Trident replacement and either go for a reserve capability or a much reduced force, and committing in more than rhetoric to the worldwide move towards a nuclear-weapons convention (see "Britain's nuclear plans: the Corbyn factor", 17 September 2015). Where the carriers are concerned, the clever thing to do would be to sell the first one to China, a move that would more or less guarantee that India would buy the second.

This approach would help create space to undertake a serious defence and security review that would go back to basics in determining what a country such as the UK could really do in terms of contributing to international peace and stability (see "Britain's defence, the path to change", 7 May 2015). At present Labour will not take such a path because it has a near-pathological fear of being labelled unpatriotic, thus leaving the party with little room for manoeuvre in a vital department.

A genuinely internationalist agenda should be central to a revised vision of security.

But the fear is mistaken, and the general election shows why. What became clear during the campaign is that Labour is steadily increasing its appeal to people under forty, including many in their teens and twenties. These represent different generations to the mostly older people who hang on to the idea of “Great” Britain as a world military power (see "In defence of greatness: Britain's carrier saga", 11 May 2012).  

The implication is that accusations of lack of patriotism, such as might still follow a genuinely radical defence review, are gaining progressively less traction within the national body-politic. If Labour recognises this, the concern about losing votes on the issue should recede. This is even more the case if three other priorities were emphasised.

First, a crucial security issue for our time is climate disruption. Second, the “war on terror” has not made people feel safer. Third, a commitment to a genuinely internationalist agenda, starting with United Nations reform and a substantial peacekeeping role, should be central to a revised vision of security. Far from being unpopular, a confident and positive approach on these themes would be attractive to the new generations of voters (see "Beyond 'liddism': towards real global security", 1 April 2010). .

One of Labour’s most remarkable achievements under Jeremy Corbyn’s leadership is that austerity is no longer seen as inevitable but rather as a failed policy. Compare the “there is no alternative” view that was dominant only a few months ago.  

A coherent effort backed by strong ideas overturned the prevailing wisdom on austerity. The irrelevance of so much of the UK's defence posture is long overdue for similar treatment. It worked once. Why not again?