Yoon Suk Yeol has become South Korea's first sitting president to be arrested after investigators scaled barricades and cut through barbed wire to take him into custody. Yoon, 64, is being investigated on charges of insurrection for a failed martial law order on 3 December that plunged the country into turmoil.

T HE PRESIDENCY of South Korea can be a treacherous job. Past office-holders have been impeached and even assassinated. But until January 15th, when investigators took Yoon Suk Yeol into custody, a sitting president had never been arrested.

The Constitutional Court, an arbiter in a polarized nation, is about to consider whether Yoon Suk Yeol’s impeachment for declaring martial law was justified.