This month’s G20 Summit in Johannesburg marked several historic firsts. For starters, it was the group’s first summit in Africa, and the first to include the African Union as a full-fledged member. It also set less encouraging precedents: It was the first meeting boycotted by a key founding member, the US, on spurious grounds, and the first in which that same country tried to prevent the host from issuing a final declaration. Equally unprecedented was South Africa’s decision to ignore Washington and issue one anyway.