This summer's hasty and poorly executed withdrawal of US forces from Afghanistan caused shock and profound unease among Washington's allies, just as they hoped the unilateralism of the Trump era had been left behind. But anxiety about America's position on defence only intensified with the unveiling in September of AUKUS - a trilateral security pact involving Australia, the US and UK covering the Indo-Pacific region. The exclusion of France from that deal not only enraged Paris but also further alarmed European allies about American intentions.

So what next? Can the Biden administration be trusted to uphold the security guarantee which underpins NATO? Or, as France's President Emmanuel Macron argues, do these and other actions by the United States show that the 70 year-old Alliance is effectively "brain dead" and that Europe has to set about achieving "strategic autonomy" without depending on Washington's whims?

In a lively forum with key players and thinkers about European security from both sides of the Atlantic, Edward Stourton considers what should happen now on European defence and whether seemingly divergent views about it can be reconciled.

Those taking part: Professor Malcolm Chalmers, Deputy Director of the Royal United Services Institute in London; Nathalie Loiseau, MEP, former French Minister of European Affairs and Chair of the European Parliament's Sub-committee on Security and Defence; Dr Constanze Stelzenmüller, expert on Germany and trans-Atlantic Relations in the Center on the United States and Europe at the Brookings Institution in Washington, D.C.; and Linas Linkevicius, former Foreign and Defence Minister of Lithuania.

Producer: Simon Coates

Photo by Dursun Aydemir/Anadolu Agency via Getty Images