Russia's use of North Korean missiles in Ukraine could be a 'cash cow' for Kim Jong Un, expert says

• Russia has used North Korean missiles in Ukraine over the past month, according to South Korea.
• Their use could help Kim Jong Un boost his missile sales, an analyst told The Wall Street Journal.
• "This is the cash cow," said Toby Dalton, a senior fellow at Carnegie Endowment.

Russia's use of North Korean ballistic missiles in Ukraine could boost missile sales for Kim Jong Un's government, a military analyst told The Wall Street Journal.