He recalls the popular challenge now underway against Omar al-Bashir’s rule in Sudan; the deaths of Kofi Annan, the first African secretary General of UN, and Winnie Mandela, a flawed leader of the South African liberation movement; the highly positive emergence of the reform-minded Abiy Ahmed, the Ethiopian prime minister; and the international attention to Congolese surgeon Denis Mukwege, who won a Nobel Peace prize for his work with rape victims.

Each Friday, I look at what the presidential contenders are saying about foreign policy. This Week: President Joe Biden imposed new tariffs on Chinese imports, raising tensions with Beijing and slowi…