On this day, 20 May 1960 mass demonstrations took place in Japan against the US-Japan (Anpo) treaty which would see US troops permanently based in the country. It was part of a huge, popular movement to prevent ratification of the deal, which severely disrupted Japanese society but ended in failure. However it did prepare the ground work for a resurgence in radicalism in 1968.
More info in this account of Japan in the 60s: https://libcom.org/history/japans-1968-collective-reaction-rapid-economic-growth-age-turmoil https://www.facebook.com/workingclasshistory/photos/a.296224173896073/1721117871406689/?type=3