President Xi Jinping ended his state visit with a parting shot for Prime Minister David Cameron, saying China sees the UK as 'an important part of the EU' and hopes it will 'promote deeper China-EU ties'. Setting aside the additional pressure this puts on Cameron to keep the UK in the EU, Xi’s intervention also exposes a deeper problem for the prime minister: the pursuit of a three-pronged foreign policy, that builds relations with rising powers like China on a par with Europe and the US, leaves the UK’s foreign policy off-balance.

First, emerging markets have entered a period of economic and political turbulence. China aside, UK exports to most of these markets, including India, Turkey, Mexico, Indonesia and Brazil, have been flat since 2011. Beijing now faces its own challenge of transitioning from manufacturing exporter to consumption-led middle income country, creating new risks as well as opportunities. Nor are these countries showing the desire to be partners to Britain on issues of global governance or in addressing international crises.

Second, the US, Britain’s key ally, is being drawn by China's rise towards the Asia-Pacific, where the UK is less relevant and away from the Middle East and Europe, which are the biggest sources of risk to the UK. The US is also increasingly resentful of what it sees as the UK’s excessive deference toward China and considers Britain’s obsession with its EU membership to be self-indulgent.

Third, at a time when Europe faces a host of complex challenges, the UK's influence in Europe is at an all-time low. David Cameron’s decision to hold a referendum on Britain’s EU membership has added to the EU’s instability at a critical juncture. Not only is it unclear what specific concessions Cameron requires in order to campaign for the UK to remain in the EU. It is also unclear what role the UK would play in the EU should he succeed.

Echoing Winston Churchill, Cameron, like his recent Labour predecessors in 10 Downing Street, persists with the idea that Britain lies in the middle of three interlocking circles of influence – Europe, the transatlantic relationship, and the country's broader international network from the Commonwealth to China. The implication is that Britain can serve variously as a pivot, bridge or connecting node in a networked world, with a foreign policy that is expeditionary and multi-directional.

Despite the UK’s many attributes as an international hub, it will not be successful acting alone as a flexible intermediary in an increasingly competitive world; to try to do so would yield ever-diminishing returns. Given the growing international competition for power and wealth and the relative decline in the UK's resources, the government should think of Britain as located at the centre of a series of concentric circles, with the EU constituting the first or 'inner circle' of its international influence.

The EU has its structural weaknesses. But if he can secure a renewed popular mandate for membership, Cameron could leverage the EU’s single market to negotiate improved terms for UK businesses to access emerging markets like China as well as established markets like the US and Japan. The EU also brings policy tools and leverage to manage the range of challenges to Europe’s south and east, including confrontation with Russia and the unprecedented inflow of refugees and other migrants.

And only by working through the EU will the UK have a chance to influence the shape of international deals on combating climate change or protecting digital privacy and an open internet. Acting alone, its voice would be diminished in each of these policy areas.

The second circle of UK influence is the transatlantic relationship, which continues to offer an essential insurance policy against major security threats. Through a Transatlantic Trade and Investment Partnership, it could also offer a structure for writing the standards and regulations for trade and investment that most if not all developed economies would adhere to, setting a benchmark for the rising economies to join.

The third circle is the UK's remaining bilateral and institutional relationships, from China and Japan to the G7, G20 and Commonwealth. In all cases, the UK's influence with and within them will be enhanced by operating from the platform of its European and then transatlantic circles.

To benefit from the leverage the EU can offer, the government first has to negotiate a settlement with its European counterparts on topics that have little to do with its international security and influence. British politicians would then have to engage in the diplomatic leg work and hard graft that would help the EU to live up to its potential.

If Britain were to leave, however, it would find itself detached from a weaker and potentially unstable EU, a junior partner to the US, and subject to the commercial whims of unpredictable rising economic powers, including, as President Xi’s visit forewarned, a more powerful and demanding China.

This article was originally published by the Telegraph.

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