Trident debate: There are 16,000 nuclear missiles in the world - but who has them, and does Britain really need its own arsenal?

The number of countries that could actually deploy a nuclear missile at short notice is remarkably small - should Britain be among them?

HMS Vanguard sits in dock at Faslane Submarine base on the river Clyde in Helensburgh, Scotland. File photo (Getty Images)

The Tories have put the issue of Britain’s Trident nuclear programme at the heart of the election debate with less than a month to go to the general election.

Michael Fallon, the Conservative Defence Secretary, has said that a Labour government would do a deal with the SNP that involves getting rid of Trident and putting Britain’s security at risk – saying Ed Miliband will “stab the United Kingdom in the back”.

Amid accusations of “mud-slinging” and Labour’s insistence that it is “crystal clear” on keeping and renewing the UK’s four operational nuclear-armed submarines, we ask the question – does Britain really need them?

How many nuclear missiles are there in the world?

While estimates vary, the most recent figure published for worldwide nuclear weapon stocks by the Bulletin of the Atomic Scientists (the best international source for such figures) is 16,300. A more recent but arguably less reliable figure from the Federation of American Scientists (FAS) puts the worldwide total at 15,650.

The flagship of Russia's Nothern Fleet, heavy nuclear missile cruiser 'Pyotr Veliky' (AFP/Getty Images)

Located across 14 countries at some 98 sites, roughly 10,000 are believed to be in military arsenals while the remaining are in storage and scheduled for dismantlement.

Of those 10,000, about 4,000 are described by the Bulletin as “operationally available”, while at any given time 1,800 nuclear weapons are held on high alert – meaning they can be deployed with just a few minutes’ notice.

Who has them?

Of the total global inventory, 93 per cent are held by the US and Russia.

Very recent figures from the Bulletin estimate that the US has 7,100 nuclear warheads, consisting of 2,080 deployed, 2,680 in storage and 2,340 retired and awaiting dismantlement. Russia – which is less open with its figures – is thought to have slightly more, around 8,000 in total.

North Korea missiles on trucks make its way during a massive military parade to mark the 65th anniversary of the communist nation's ruling Workers' Party in Pyongyang, North Korea (AP)

The UK has about 215 warheads in total, though it relies heavily on the US to maintain them. Each of its four nuclear submarines carries 16 Trident missiles at any given time.

France has 300 warheads, some of which are deliverable by aircraft. Like the UK, it has one nuclear-armed submarine on patrol at all times.

China only has about 250 warheads, and none of them are thought to be fully deployed according to the FAS. China is believed to be in the process of increasing its arsenal.

The most recent update on Israel suggests it has 80 nuclear warheads, though the country officially neither confirms nor denies their existence. The FAS says Pakistan has around 100-120, India 90-110, and North Korea fewer than 10, none of which have been made operational.

Who wants them?

According to the International Campaign to Abolish Nuclear Weapons (ICAN), there are now some 40 countries that have nuclear power or research reactors capable of being diverted for weapons production.

Pakistan and North Korea are the only countries to recently join the so-called nuclear weapons club, while Iran’s new nuclear deal makes its chances of joining in the near future remote.

Libya, which bought details of Pakistan’s nuclear programme from defecting scientist Abdul Qadeer Khan, abandoned its attempts under pressure from the US.

Iranians celebrate in northern Tehran following the announcement of Iran's nuclear agreement with world powers (AP)

According to Forbes, Syria attempted to build a secret weapons reactor with the assistance of North Korea but it was bombed by Israel in 2007 before much progress had been made.

In addition, fears that nuclear energy programmes can easily lead to weapons programmes are unfounded – it is reportedly possible, but not practical, and has never been achieved.

In other words, the reality of nuclear proliferation in the world right now is fairly limited – suggesting the efforts of the International Atomic Energy Agency have been “diligent and pretty effective”, says nuclear scientist James Conca.

So does Britain need them?

Michael Fallon today described £25 billion to refurbish the Trident programme as “a price well worth paying to keep this country safe”.

Britain's Defence Secretary Michael Fallon (Getty Images)

It’s a conservative estimate (with both a lower- and upper-case ‘C’) however. Paul Ingram, the director of the thinktank BASIC (The British American Security Information Council), says that when often-forgotten decommissioning work is included the capital cost of the new system will total £50.6 billion between 2012 and 2062.

BASIC was responsible for setting up the independent all-party Trident Commission, which last summer issued a report setting out the verdict of MPs on whether Britain still needs a nuclear deterrent of its own.

Its headline discovery was that Trident isn’t really that independent at all – if the US were to ever remove its support and know-how, the UK’s nuclear capability would collapse in a matter of months.

Nonetheless, in the short term at least, the commission found that even the slimmest of chances Britain could face “strategic blackmail or nuclear attack” made it “imprudent” to abandon Trident.

“If there is more than a negligible chance that the possession of nuclear weapons might play a decisive future role in the defence of the United Kingdom and its allies” then they should be retained, the report said.

Faslane Naval Base on the Gare Loch in Scotland (Getty)

But what do the British public think? In Scotland – which houses the Trident submarines at Faslane – the strongly pro-disarmament SNP is on course to win 40 of 59 seats, according to the latest polls.

In 2009, a ComRes poll for The Independent asked: “Given the state of the country’s finances, should the Government scrap the Trident nuclear missile system?” Of all respondents, 58 per cent said “Yes”, 35 per cent “No”, while just 7 per cent said “Don’t Know”.

Mr Fallon says security will be the key issue at the heart of the election in 28 days’ time. The question of Trident is, if nothing else, polarising.

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