Let's stay in Europe—and lead on a new defence policy for the continent

We’re set to leave the EU at a moment of extraordinary geopolitical tumult. A transatlantic trade war looms, President Trump postures against America’s traditional allies, and Russia and China are probing Europe’s soft spots. No wonder European defence is finding a second wind.

Military spending on the continent is rising faster than anywhere else, and concrete new initiatives—like -Permanent Structured Co-operation, which covers logistics, maritime surveillance and more—are firming up.

As former MI6 chief John Sawers told Prospect in February, Britain risks sliding “adrift” into a third tier of powers in this fragmenting world.

This creates one of the many ironies of Brexit: a newly lonely UK, once the most dogged sceptics of EU defence co-operation, is belatedly realising its value, and clambering to keep a foothold.

Staying inside would allow the UK to keep a pivotal role in areas like the Galileo satellite system, and see off talk of blowing billions on an unnecessary alternative.

It would enable access to cash from pots like the €4.5bn European Defence Fund, rather than having British firms being squeezed out by “buy European” rules. And it would permit continued British leadership of the anti-piracy mission in the Horn of Africa.

Critics dismiss EU defence policy because Nato does the heavy lifting. The EU is unlikely to wade into high-intensity combat, but carefully-calibrated joint action on the continent’s troubled peripheries could become increasingly important.

Without the UK involved, the burden of that will fall very heavily on very few states, notably France and Italy. So the EU would struggle to turn its ambition of “strategic autonomy” into reality.

The open tensions at the recent Nato summit, and the impact of Trump’s meeting with Vladimir Putin on the European security order, means that both Britain and Europe need one another’s help on defence, to hedge against an unpredictable America. Were the UK to stay in the EU after all, it could take a leading role in forging a new defence policy for the continent.