In his statement to the Commons, the prime minister made no mention of two of the most significant features in the Integrated Review of the UK’s security, defence, development and foreign policy, which was being published as he spoke. These features are the increase in Britain’s stockpile of nuclear warheads and the implicit downgrading of the Middle East as a primary region of strategic focus.

Of course, the Middle East does receive occasional – and mostly cursory – mention (14 times across 114 pages) in the report. There are glancing references to instability there and the consequent threat of terrorism, support for girls’ education, a desire to increase British investment in the region and to help with “green innovation” (there must be eager excitement about that in Riyadh). The theatre of active operations in the region is dealt with in one sentence – “Our armed forces will continue to contribute to the Global Coalition against Daesh in Iraq and Syria” – and the problem of Iranian nuclear ambitions and “destabilising activity” likewise gets a sentence.

From this, the conclusion is clear. Britain cannot afford to be over-committed in three different geographically-defined contests (facing Russia in Europe and the Atlantic; with or within Arab states in the Middle East; keeping tabs on China in Indo-Pacific). Something had to give. And since sending aircraft carriers to the South China Sea is the future, prioritising the Middle East must be confined to the past.

The release of the defence command paper next Monday should provide a clearer sense of resource priorities. Providing an overview of threats and priorities from now until 2030 necessarily calls for the broadest of brushes and there is, understandably, plenty of those strokes in the Integrated Review, titled Global Britain in a Competitive Age.

the South China Sea is the future, the Middle East must be confined to the past

But despite the temptations of the deepening engagement in the Pacific – from joining the Trans-Pacific partnership in some shape or form to countering (also in some shape or form) Beijing’s burgeoning self-confidence – the Integrated Review makes clear that, first and foremost, the UK’s primary focus remains the threats on its own European continent. That means Russia which the Review describes as “the most acute threat”.

Fear of Moscow is at the heart of the Review’s most startling announcement – that the number of Britain’s Trident nuclear warheads may increase by up to 40 percent.

Until now, the UK’s stated intent was to reduce its stockpile from 225 to 180 by the middle of this decade. The Review announces a complete reversal of this goal, instead setting a new cap of 260 nuclear warheads. Following the report’s publication, Downing Street sources were at pains to brief that raising the cap was not the same as committing to possess 260 nuclear warheads, merely that the ultimate number would not exceed that stated maximum. But the re-direction of travel is clear.

The report justifies the u-turn as a “recognition of the evolving security environment, including the developing range of technological and doctrinal threats.” Plus ça change? Reminding the public about the bargaining power of nukes, Dominic Raab told Radio 4’s Today programme on Monday that “circumstances change and the threats change” and increasing the nuclear deterrent was “the ultimate insurance policy against the worst threat from hostile states.”

Outrage has come from predictable quarters. The SNP condemns Scotland having to play host to more nuclear weapons. This is a major issue for the Scottish Nationalists. In the event of Scottish independence, they are committed to closing the nuclear submarine base at Faslane on the Clyde upon which Britain’s deployment of Trident currently depends (no other sight in the British Isles has been established as a suitable replacement, which is one more reason for why Scottish politics matters).

Britain will still have fewer nuclear warheads than France

Other anti-nuclear campaigners have voiced their abhorrence at the nuclear escalation, some suggesting it is a breach of Article 6 of the UN-sponsored nuclear non-proliferation treaty (NPT), to which Britain has been a signatory since 1968.

Is this so? Article 16 states that signatories undertake “to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control.” Britain will continue to argue (as it has done since 1968) that like St Augustine’s approach to chastity, it does seek nuclear disarmament but, given the state of the world, not yet.

The precedent is clear, but context is also required. Even if the British accelerated their warhead acquisition programme fully to the new cap, it would still represent a fraction of the global stockpile of nuclear weapons, estimated at around 13,500 warheads. Of these, 90 percent are Russian and American. Russia has approximately 6,500 such warheads, of which about 2,000 are effectively mothballed, although not dismantled.  Assessments vary, but China is assumed to have less than 400, perhaps 350, in total.

An increase up to the cap of 260 would still mean that Britain had fewer nuclear warheads than its most obvious comparable ally, France. Thirty years ago, France had an arsenal of over 500 such warheads. With the Cold War’s end, the number was steadily reduced. In 2008, President Nicolas Sarkozy declared that the stockpile would be shrunk further to below 300. Currently undergoing an extensive modernisation programme, it is not likely to fall any further below its current number of around 290, all of which are deployed and operational (most of them in France’s Triomphant class of nuclear submarines; but also from 40 Rafale F3 aircraft).

Given his desire to reposition Labour away from its recent Corbynite past and demonstrate support for renewing Trident, Keir Starmer is reluctant to make too big an issue of why Britain is increasing its nuclear arsenal. In response to Boris Johnson’s statement on Tuesday, the Labour leader confined himself to regretting the Integrated Report’s failure to explain “when, why, or for what strategic purpose” the increase was necessary. These are questions that deserve better answers than the government has troubled itself to provide.

But one factor should be noted. In the European theatre, the balance of tactical nuclear warheads is heavily loaded in Russia’s advantage. The collapse of US-Russian cooperation since 2013 means that the exact number of nuclear warheads Russia is targeting on Europe is unclear. The Pentagon assumes that Russia has perhaps 2,000 tactical nuclear weapons, vastly outnumbering the NATO response. Having abandoned its last British nuclear missile base at Lakenheath in 2006, the United States retains no more than 150 tactical nuclear warheads in Europe, mostly stationed in Turkey and Italy. These tactical warheads are reliant on being dropped by aircraft that would struggle to penetrate Russian air defences.

The British Army’s current artillery deployment in the Baltic States is intended to deter a Russian invasion there. It is not on a scale that would deter the Russian advance for long, should Moscow deem the gain worth the gamble. There are good reasons for questioning how sensible NATO would be in using tactical nuclear weapons to frustrate the Russians marching on Tallinn, not least because of the damage they would do to the country being defended. But Britain’s £24 billion increase in defence spending is to be accompanied by a shrinking – not an expansion – in the ranks and no conventional war against Russia in Eastern Europe is going to end well for the NATO deployment there given the existing or future balance of forces.

Reading between the lines of Global Britain in a Competitive Age, this would partly explain the inferiority for which the expansion of Britain’s nuclear arsenal seeks to compensate. If Boris Johnson and Dominic Raab will not articulate the intention clearly, will the Defence Secretary, Ben Wallace, put us in the picture?