North Korean Premier Pak Thae-song will arrive in China on Friday for a three-day trip to mark the anniversary of a friendship treaty between the two countries, in another sign of improving ties between the two traditional allies. This year is the 65th anniversary of the signing of the China-North Korea Treaty of Friendship, Cooperation, and Mutual Assistance, Beijing’s only formal defence pact, and Pak will be at the head of a party and government delegation. “China and North Korea are...