Who Oversaw Japan's Demilitarization After WWII? SCAP & MacArthur

The **Supreme Commander for the Allied Powers (SCAP)** directed Japan's demilitarization from **September 2, 1945 to April 28, 1952**. **General Douglas MacArthur** served as Supreme Commander throughout the occupation.

SCAP Structure & Authority

• Headquarters: Dai-Ichi Building, Tokyo
• Authority: Directives to Japanese government (not military government — Japan retained sovereign administration under SCAP supervision)
• Staff: ~3,000 military/civilian personnel (US-led, with British Commonwealth, Soviet, Chinese representatives on Advisory Council)

Demilitarization Actions

• Constitutional: Article 9 (1947 Constitution) — "forever renounce war... land, sea, air forces never maintained"
• Military disbandment: Imperial Japanese Army & Navy dissolved (1945); 7M+ soldiers demobilized
• Industrial dismantling: Zaibatsu dissolution; arms factories converted/reparations; aircraft, shipbuilding, heavy machinery capacity reduced
• War crimes trials: IMTFE (Tokyo Trials) — 28 Class A defendants; 7 executed (including Tojo)
• Purge: 200,000+ militarists/nationalists removed from public office
• Education reform: Militaristic curriculum removed; pacifist/constitutional education mandated

Evolution: Reverse Course (1947–50)

• Cold War → US wants Japan as anti-communist bulwark
• 1950: National Police Reserve (75,000) → **1954: Japan Self-Defense Forces (JSDF)**
• SCAP ends (1952); US-Japan Security Treaty permits US bases; JSDF expands incrementally

Legacy

SCAP's demilitarization was **unprecedented in thoroughness**—a total society transformation. Article 9 remains (reinterpreted 2014 for collective self-defense). MacArthur's role: **proconsul with near-absolute authority**, simultaneously democratizer and Cold War architect.