OKINAWA, JAPAN - DECEMBER 13: Anti U.S. Base protesters stage a rally outside the U.S Base Camp Schwab on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)

OKINAWA, JAPAN - DECEMBER 13: Anti U.S. Base protesters stage a rally outside the U.S Base Camp Schwab on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)

NAGO, JAPAN - DECEMBER 13: In this aerial image, land reclamation work continues at Henoko district on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)

NAGO, JAPAN - DECEMBER 13: In this aerial image, land reclamation work continues at Henoko district on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)

OKINAWA, JAPAN - DECEMBER 13: Anti U.S. Base protesters stage a rally outside the U.S Base Camp Schwab on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)

OKINAWA, JAPAN - DECEMBER 13: Anti U.S. Base protesters stage a rally outside the U.S Base Camp Schwab on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)

OKINAWA, JAPAN - DECEMBER 13: Anti U.S. Base protesters stage a rally outside the U.S Base Camp Schwab on December 13, 2018 in Nago, Okinawa prefecture, Japan. Tensions between the central government and Okinawa rose further as reclamation work will start throwing in sand and earth (into the sea) on Dec. 14. (Photo: Richard Atrero de Guzman/ AFLO)