• Vice President Mike Pence called North Korea’s missile test “a provocation” as he started a 10-day tour of Asia with a trip to South Korea. Above, Mr. Pence at the Seoul National Cemetery.

The failed test, a deep embarrassment for the North’s leader, Kim Jong-un, has not quelled fears of U.S. military action. A mix of national ambitions, personal ego and deadly weapons is creating opportunities for miscalculation.