One of the great rules of investing is that things are never as bad as they seem, nor as good. Perhaps the most famous contrarian maxim of them all – Warren Buffett’s “buy straw hats in winter” – neatly sums up the idea that wild swings in sentiment create risks and opportunities for investors to assess.

And it’s in exactly this spirit of rationalism that investors should approach the explosive debate US President Donald Trump has kicked off about the validity of the ESG (environmental, social and governance) and DEI (diversity, equity and inclusion) movements.