It's impossible to predict Donald Trump's policy-making and diplomacy. He seeks neither consistency, nor consensus - as is obvious in his approach to China, North Korea, Iran and other challenges at home and abroad. Stephen Sackur speaks to Republican Senator Rick Scott of Florida - a key Trump ally back in 2016, who has since parted company with the President on some of his most controversial policies. How effective and how sustainable is the Trump presidency?

(Photo: US Senator Rick Scott speaks during Concordia Americas Summit, in Bogota, Colombia, 2019. Luisa Gonzalez/Reuters)