If Britain’s Labour government is looking for it, there is a gaping door back into a new relationship with Europe – defense cooperation.

And this door has the added advantage that increased defense cooperation between Britain and its European NATO allies is becoming essential to counter growing American disillusionment with Europe.

Whether it is a MAGA-fied isolationism or a pivot to Asia, it is clear that foreign policymakers in both the Democratic and Republican parties are questioning America’s commitment to Europe.

For those on both sides of the English Channel this creates an opportunity to start to repair the damage of eight years of Conservative Party Brexiteering. It could also strengthen European defences and, ironically, help to retain the American nuclear umbrella.

Europe faced the problem of American isolationism and problems with Asia before—in the run-up to the creation NATO and within a year of its founding. When the idea of linking America to the defense of post-war Europe was first mooted, Senator Arthur Vandenberg, leader of the Republican-controlled Senate, insisted on proof that the Europeans were jointly committed to their own defense.

This was proven by British Foreign Secretary Ernest Bevin with a 50-year Anglo-French Treaty of Alliance and Mutual Assistance in 1947 and then a year later with an extension of the mutual defense pact to include Belgium, the Netherlands and Luxembourg. Vandenberg and the Republicans were impressed, and on April 4, 1949 the North Atlantic Treaty was signed.

A year later Europe panicked when North Korea invaded South Korea. What if the Soviet Union took advantage of Korea to attack Europe? Could America afford to fight on two fronts? Which was the more important to Washington—Europe or Asia? The result was the Pleven Plan (named after French Prime Minister Renee Pleven). It proposed strengthening the European arm of NATO with a European Army headed up by a European defense minister.

The Pleven Plan was killed off by the French National Assembly and Europe grew increasingly dependent on the United States, especially its nuclear umbrella.  Now – nearly 75-years later – Europe faces a similar set of circumstances. A populist Donald Trump is questioning the value of NATO and threatening to refuse to defend members who fail to spend at least two percent of their GDP on defense.  On the other side of the political aisle, the Democrats are as obsessed with the Chinese threat as the Republicans. The Asia Pivot started with Barack Obama. Meanwhile, Russia has invaded Ukraine and Europe worries that Moscow’s success there will lead to attacks elsewhere.

Britain has played a leading role in chivvying the West to defend Ukraine and the EU has more or less matched the Americans in the supply of aid to Kyiv. But the wider issue of defending European NATO remains in the balance and Britain can play a crucial role in resolving the problems.

The key is Britain’s nuclear weapons which must remain in place if Russia is to continue to be deterred. Britain has 250 nuclear warheads based on four Trident nuclear submarines. They are already committed to the defense of NATO, but they are under the operational command of the British Prime Minister. Britain should investigate ways to further commit its nuclear arsenal to Europe, perhaps in coordination with the French.

There is already a nuclear Anglo-French cornerstone which can be built upon. In 2010 David Cameron and French President Nicolas Sarkozy signed a deal which established cooperation on nuclear issues starting with a joint simulation centre for the testing of nuclear warheads. It was a first, and both sides recognised it as a starting point. At the time there was even talk of joint nuclear submarine patrols.

Anglo-French cooperation would double a European nuclear deterrent. It would still only be one-sixth the size of the Russian nuclear arsenal and there would need to be a shift from the policy of MAD (Mutual Assured Destruction) to MIND (Minimum Deterrence). But then the Chinese will able to hold off the Soviets with only 300 warheads at the height of the Sino-Soviet split. To insure the success of a MIND policy A European NATO would have to agree to threaten a conventional weapons attack by Russia with immediate nuclear retaliation.

But that may not be necessary. Even a MAGA-fied America probably wouldn’t break its long alliance with Britain. In the early days of the Common Market, Europeans fretted that admitting Britain would also let in a fifth-column—the United States. This time around, they might find that column useful if it gave a European NATO continuing access to American capabilities.

Britain could be out of the EU but connected to Europe through membership of a European NATO and most likely allied to America by a separate treaty. An attack on a European country would draw in Britain and the follow-up attack on Britain would draw in America. It would not be the clear diplomatic chain of command of today’s NATO, but, at the very least, a Vladimir Putin couldn’t be confident that the US would do nothing if he attacked Europe.

And at the same time, Britain’s military links would have secured a vital link with Europe which could come become the basis of a new, wider relationship.

* Tom Arms is foreign editor of Liberal Democrat Voice and author of “The Encyclopaedia of the Cold War” and “America Made in Britain". To subscribe to his email alerts on world affairs click here.