Australian Treasurer Jim Chalmers says that Australia will "quite dramatically" boost its defense spending, while working with other Group of 20 nations to improve cooperation to combat volatility. Chalmers also warns that he sees US tariffs levied on countries around the world by President Donald Trump as an act of "economic self-harm." He speaks with Bloomberg's Oliver Crook on the sidelines of a meeting between many of the world's most powerful finance ministers in South Africa.