With relations between the United States and North Korea still in disarray after an abrupt ending to their recent summit in Hanoi, North Korean leader Kim Jong Un is reaching out to another partner: Russia. On April 25, Kim will hold his first summit with Russian President Vladimir Putin. The Putin-Kim summit is finally going ahead after a serious of delays, during which time North Korea's leader conducted high-profile regional trips to South Korea and elsewhere. Thanks to its decadeslong ties with North Korea, Russia has become both an economic and diplomatic lifeline for the oft-embattled regime, even if Beijing long ago supplanted Moscow as Pyongyang's major ally. While sanctions against North Korea, as well as Russia's economic malaise, will limit what Moscow can tangibly provide to Pyongyang, the Vladivostok summit will highlight the host's role as a potential counterbalance to both China and the United States and a possible...