For decades before the Korean War, it was possible to travel from what is now South Korea to Europe by train. And for a brief period in 2018, the two Koreas made progress on re-opening that route for the first time since the division of the peninsula, with a South Korean delegation inspecting some 1,600 miles of North Korean railroads.

Yet while two Koreas’ leaders identified railway connections as a key area of cooperation at their summit in April 2018, there has been little progress on the inter-Korean railway project in the years since, as virtually all diplomacy between