Jeff J. Mitchell / Getty How Washington owns the UK’s nukes London’s nuclear dependency cuts to the heart of the US-UK Special Relationship.

LONDON — In the run-up to the British general election, there has been intense debate about the future of Trident, the United Kingdom’s nuclear weapons program, which will reach the end of its serviceable life in 2026. Party leaders in the next parliament must decide whether to scrap it, replace it with a scaled-back alternative, or update it.

But there is one simple question that nobody is asking. When is an independent nuclear deterrent not an independent nuclear deterrent?

To many experts, the answer is all too obvious: when the maintenance, design, and testing of UK submarines depend on Washington, and when the nuclear missiles aboard them are on lease from Uncle Sam.

No British politician is addressing this issue, and it shows. Informed voters are probably familiar with the various parties’ declared stances on the Trident question, but few Britons have any idea that the United States is even involved in the program, let alone their country’s nuclear benefactor.

Instead, Trident is being presented as a purely domestic matter, and one of the few in modern British politics that puts clear ideological water between Left and Right. The Tories have pledged £100 billion ($154 billion) to upgrade the program. The insurgent Scottish Nationalists — who will probably hold the balance of power in the likely event of a hung parliament — want to scrap the weapons altogether (the nukes are based in Scotland), as do the Greens and Plaid Cymru. The remaining parties fall somewhere in between.

At a deeper political level, however, Trident cuts to the heart of the US-UK Special Relationship, and its contrasting significance for London and Washington.

In 2006, Parliament’s Select Committee on Defense presented a White Paper to Parliament containing a granular analysis of the Trident program. Although it is now almost a decade old, NATO sources have confirmed that the paper remains the benchmark for non-classified information on Britain’s nuclear weapons, as very little has changed since. And it lays bare the extent of the UK’s nuclear reliance on America.

The report makes for striking reading. The UK does not even own its Trident missiles, but rather leases them from the United States. British subs must regularly visit the US Navy’s base at King’s Bay, Georgia, for maintenance or re-arming. And since Britain has no test site of its own, it tries out its weapons under US supervision at Cape Canaveral, off the Florida coast.

A huge amount of key Trident technology — including the neutron generators, warheads, gas reservoirs, missile body shells, guidance systems, GPS, targeting software, gravitational information and navigation systems — is provided directly by Washington, and much of the technology that Britain produces itself is taken from US designs (the four UK Trident submarines themselves are copies of America’s Ohio-class Trident submersibles).

The list goes on. Britain’s nuclear sites at Aldermaston and Davenport are partly run by the American companies Lockheed Martin and Halliburton. Even the organization responsible for the UK-run components of the program, the Atomic Weapons Establishment (AWE), is a private consortium consisting of one British company, Serco Group PLC, sandwiched between two American ones — Lockheed Martin and the Jacobs Engineering Group. And, to top it all, AWE’s boss, Kevin Bilger — who worked for Lockheed Martin for 32 years — is American.

The UK Government emphasizes that Britain’s Trident submarines are "operationally independent," meaning that they have an all-British crew and take commands only from the Prime Minister, regardless of whether he is coordinating with NATO and the White House. Some believe that this safeguard is sufficient to counteract Washington’s dominance of the program.

"Just because my car is made in Japan or Germany, doesn’t mean it’s not my car to drive," says Thomas Karako, a senior fellow with the International Security Program and the Project on Nuclear Issues at the Center for Strategic and International Studies (CSIS) in Washington, DC. "Do I need to make my own filing cabinet to have an independent office?"

In this view, operational independence is "the most important thing," and the US has no reason to use Britain’s nuclear program as a military proxy.

“It is in America’s interest to have an independent nuclear actor in the region, so that it complicates the decision-making for an aggressor,” Karako says. “Any attack on one NATO ally would raise the risk of retaliation from another under Article Five, and it’s not a case of piling all the responsibility on the United States. That will only work with operational independence.”

But some other experts are deeply skeptical about the current state of affairs. “As a policy statement, it’s ludicrous to say that the US can effectively donate a nuclear program to the UK but have no influence on how it is used,” says Ted Seay, senior policy consultant at the London-based British American Security Information Council (BASIC), who spent three years as part of the US Mission to NATO.

"The fact that the US is spending so much on producing, leasing, maintaining the car — let’s talk before you drive it into a brick wall," he says. "But this isn’t Hertz rent-a-car we’re talking about. This is the end of the world."

Seay added: "It would also be unthinkable for the UK to launch a strike outside of NATO. There is an incredible pressure on every member to conform. I know that as an insider. If you’re thinking about launching nuclear weapons at Russia or perhaps Iran, it has to be fought out around the NATO table. To say that you could launch a unilateral attack over the heads of NATO and Washington might be theoretically true, but practically speaking it’s rubbish."

In addition, Seay says, Washington’s influence on Trident means that it has a de facto power of veto.

“There is no uniquely British component in the whole thing,” he points out.

"If the US pulled the plug on the UK nuclear program, Trident would be immediately unable to fire, making the submarines little more than expensive, undersea follies."

The 2006 White Paper underscores this point. “One way the USA could show its displeasure would be to cut off the technical support needed for the UK to continue to send Trident to sea,” it says.

"The USA has the ability to deny access to GPS (as well as weather and gravitational data) at any time, rendering that form of navigation and targeting useless if the UK were to launch without US approval."

Still, the UK Government stands by the principle of operational independence. British officials are currently in “purdah”, meaning that they cannot make any on-the-record comment to the press until after the election. But when POLITICO approached the Ministry of Defense for comment, it pointed towards a statement made in Parliament by the Minister for Europe, David Lidington, in November.

“Only the Prime Minister can authorize the employment of the United Kingdom’s nuclear deterrent, and there are no technical means by which the United States could negate or override a prime ministerial instruction,” he said.

From a fiscal point of view, he added, it is “common sense” for Britain to work with the US, “rather than incurring the extra costs ourselves.”

Professor Malcolm Chalmers, special adviser to the UK Parliament’s Joint Committee on the National Security Strategy and Director of UK Defense Policy Studies at the Royal United Services Institute (RUSI) argues that the founding principle of Trident allays fears of an undue American influence.

Unlike American nuclear systems, he says, Trident is not designed to allow a “first strike” capability, but merely to act as a deterrent. It would only ever be used to respond to a nuclear attack. If such a situation arose, Chalmers says, “concerns over the US reaction would be the least of the concerns of a UK government seeking to deter the destruction of its people.”

Be that as it may, when POLITICO discussed the matter with UK officials, all were happy to talk about what would happen in the event of a nuclear confrontation, but all refused to even speculate about what would happen if the Special Relationship deteriorated — a possibility the dismissed as purely hypothetical.

Chalmers, for instance, described a nuclear conflict as “not a likely scenario, but it is perhaps plausible.” When it came to the potential deterioration of the Special Relationship, however, he struck a very different note.

“If the US were to cut off nuclear aid now — after almost 60 years — it would be such an antagonistic act as to throw the wider alliance relationship into question,” he said. “I see no prospect that this will happen.”

Moreover, according to Peter Burt, research manager at the campaign group Nuclear Information Service (NIS), the US-UK Mutual Defense Agreement – a 1958 treatise that allows nuclear co-operation between the two nations – is “pushed through” without proper parliamentary scrutiny whenever it is due to be renewed.

“In 2014, it was extended for ten years with minimal discussion in Parliament,” he says. “No formal vote was given, and the Government made no attempt to get a proper mandate. It’s basically a done deal. The UK Government avoids shining a spotlight on its lack of nuclear independence because it’s cheaper to buy technology off-the-shelf from America than pay for research and development.”

This is understandable. The UK has invested countless billions in its nuclear deterrent, most of it funneled into American coffers. So it is natural that officials emphasize the threat — a possible nuclear holocaust — while downplaying the vulnerabilities of a strategy that puts all Britain's eggs in Uncle Sam’s basket.

At root, Trident can be seen as a microcosm of the imbalance and anxiety at the core of the relationship between a declining former empire and a reigning superpower.

“The fact that, in theory, the British Prime Minister could give the order to fire Trident missiles without getting prior approval from the White House has allowed the UK to maintain the façade of being a global military power,” the White Paper concludes.

“In practice, though, it is difficult to conceive of any situation in which a prime minister would fire Trident without prior US approval… the only way that Britain is ever likely to use Trident is to give legitimacy to a US nuclear attack by participating in it,”as was the case in the invasion of Iraq.

More than a decade later, the 2003 Iraq war continues to influence the attitude of the junior partner toward the senior. This could be seen during the opposition leaders’ debate earlier this month, when Ed Miliband, the Labour leader, revealed his desire to recalibrate Britain’s attitude towards America were he to be elected.

“We need to work with the US, but we need to work not for our allies,” he said. “I think it’s very, very important that we learn the lessons of the 2003 Iraq war, because Britain’s national interest often coincides with America’s national interest, but not always. We need a prime minister that’s willing to say no when appropriate, and that’s what I’ll do.”

Miliband then — rather hyperbolically — seized credit for the White House’s decision not to bomb Syria in 2013, claiming that his opposition to military action influenced the vote in the British parliament, which in turn influenced President Obama.

By contrast, when Prime Minister David Cameron visited the White House in January, journalists asked whether the President called his opposite number "bro," as Cameron himself had suggested. Obama stepped up to the plate.

"Put simply, David is a great friend," he said. “He is one of my closest and most trusted partners in the world… Great Britain is our indispensable partner, and David has been personally an outstanding partner — and I thank you for your friendship."

When viewed in the light of the geopolitical reality, however, the President’s praise rings differently. A secret document drawn up in April to brief the US Senate and House of Representatives on the impact of the UK election revealed a harder truth: "The UK may not be viewed as centrally relevant to the United States in all of the issues and relations considered a priority on the US agenda."

For those still smarting from the Iraq debacle, when smaller Britain was derided as the America’s foreign policy "poodle," London’s nuclear dependency on Washington is troubling. For the British Government, however, Trident assures the UK of both a seat at the top table and an added dimension of security in an uncertain world — even if ministers must gamble that the Special Relationship will be more reliable than the prospect of nuclear war.

Jake Wallis Simons is a British journalist and broadcaster specializing in policy and global affairs.

This story has been updated to add information on the US-UK Mutual Defense Agreement.