ALBAWABA—South Korea is witnessing unprecedented political and military upheaval as President Yoon Suk Yeol declared martial law, marking the first such measure since 1980. The declaration comes amid claims of "anti-state" activities by opposition leaders, escalating tensions across the country. Military helicopters were seen circling the National Assembly in Seoul as special forces attempted to breach the building. Opposition leader Lee Jae-myung of the Democratic Party denounced the declaration as ...