Lang: John McCallum's China gaffe shouldn't obscure his successes

It’s been said that candour is fatal to diplomacy.
Whether owing to candour, “freelancing,” or wishful thinking, John McCallum lost his job last week as Canada’s ambassador to China over ill-judged public remarks relating to the case of Meng Wanzhou, the detained Huawei executive who is the subject of a U.S. extradition request.
To some, McCallum’s comments are just the latest in a career plagued by verbal gaffes. True enough. He was never able to master the essenti