Over the past 30 years, ministerial responsibility for New Zealand’s foreign affairs has changed hands remarkably rarely. Since 1990, just four individuals have dominated the portfolio – Don McKinnon (1990-1999), Phil Goff (1999-2005), Winston Peters (2005-8 and again from 2017 to 2020) and Murray McCully (2008-2017). Only two others have held the role, and then …