He's just walked back on those statements. Why is Japan being so passive aggressive and coy about it ? They probably think that they can scare China with that type of behavior. Japanese know a trade embargo from China will set back another decade.
In the past, Japan used to be backward and inferior to China, they sent emissaries to China to learn culture and technology from China. After that, they began to repeatedly try to attack Korea and China, organize groups of bandits to raid the Chinese coast, invade China's interior.
By the 19th century, Japan began to learn from the West and became rich and civilized. The Japanese began the policy of expansion, attacking, pillaging, massacring China, and finally attacking and provoking the West.
World War II, Japan was defeated by the US, deprived of many territories, they were humiliated and raped by the Americans. Japan is very patient, they are learning from the Americans. The United States is their master now, but they will behead America if they have a chance to rise again.
Japan is a combination of GouJian and Lubu. Patience, calm and betrayal.