Regardless of who succeeds as the new secretary general, the real issue is what the job is for. By Amir Taheri, Gatestone Institute As António Guterres, the United Nations secretary-general, will soon start clearing his desk and prepare for retirement, assessments of his tenure vary between “passable” and “mediocre.” There are those who appreciate his passionate defense of the Palestinians and critical stance on the Israel-US war against Iran. T…