Between rusting factories and peeling housing blocks were glimpses of everyday life, as North Koreans eked out their living by hauling timber and burning crop fields. In one town, two goods trucks waited patiently on a bridge into China – a sign of resumption in the cross-border trade crucial to Pyongyang’s moribund economy.

Beyond the eagle-eyed guards, portraits of the ruling Kim dynasty watch over the populace, while monumental propaganda banners laud their socialist…