President Xi Jinping is heading to North Korea on Monday with the aim of proving that China remains the best prospect for reviving his host country’s economy. The visit, Xi’s first in seven years, will focus on reinforcing ties with Pyongyang at a time when the denuclearisation of the Korean peninsula appears increasingly out of reach, according to analysts. The carefully timed sequence of diplomatic meetings also reflects Beijing’s growing confidence on the world stage and its ability to engage...