What a difference a decade makes. Back in September 2010, Guido Mantega, Brazil’s then-finance minister, was complaining bitterly about “currency wars”, and claiming the Federal Reserve’s ultra-loose monetary policy of the time was unfairly hurting his economy. “We’re in the midst of an international currency war, a general weakening of the currency,” he said then. “This threatens us because it takes away our competitiveness.” Fast forward to December 2019,…