Japan is not fully sovereign because it is keeping the US troops on its territory.
Japan is a fully sovereign state recognised by the international community.
US military presence in Japan is regulated by the 1954 Mutual Defense Assistance Agreement.
The Constitution of Japan forbids the formation of traditional military force. Read more by the Council of Foreign Relations.
The disinformation message appeared as the TV show participants discussed the annual video conference of the President of the Russian Federation Vladimir Putin, and his response regarding the question of Kuril islands. Alleged lack of Japan's sovereignty is discussed as an obstacle to negotiations regarding the Kuril islands dispute.