The global economy braced for fresh turbulence on Saturday as sweeping new US tariffs took effect, igniting tensions with key allies and trade partners. A 10 per cent “baseline” tariff was officially imposed at midnight across US ports and customs points, hitting goods from countries including Australia, the UK, Colombia, Argentina, Egypt and Saudi Arabia. The next in line, will be 57 nations, including key US allies such as the UK, Japan, India and the entire European Union facing even more punishing levies—ranging from 11 per cent to a staggering 50 per cent— starting next week, and further escalating trade...