Washington | A top Macquarie Group economic strategist has warned that US President Donald Trump’s shock 50 per cent tariff on Brazil represents a worrying pivot in his trade war towards targeting countries for their domestic politics.

Global foreign exchange and rates strategist Thierry Wizman said the aggressively high rate threatened against South America’s largest economy set a “scary precedent” because of how Trump linked it directly with what he claims is “a witch hunt” against former right-wing president Jair Bolsonaro.