HR McMaster, US National Security Adviser, 2017 - 2018

Donald Trump hasn't yet accepted it, but he'll be out of the White House in January. Gone but not forgotten. His legacy can be seen in a divided body politic, strained international alliances and deep uncertainty about America's geopolitical ambition. HARDtalk's Stephen Sackur speaks to Lt. General HR McMaster who served as Mr Trump's National Security Adviser until he was fired in 2018. In terms of America's role in the world, will the Trump years be seen as an aberration or a marker of underlying change?