Pyongyang blew up key road and rail links to South Korea on Tuesday, after warning it would take steps to cut ties with Seoul. The blasts make little difference in practical terms, because the countries are already separated by one of the most heavily fortified borders in the world. But it comes as tensions have soared on both sides of the divide. FRANCE 24's Sharon Gaffney asked University of Leeds' Korea expert Aidan Foster-Carter for his take on the latest escalation.