There is an argument in Japan to create an intelligence organization for the foreign matter, which should be membered by the police officers experiencing to work abroad. They are basically categorized as an officer who has worked as a secretary at the embassy. This assertion includes many points to be analyzed in the detail.
The electromagnetic wave was definitely availed by a small circle at the Japanese police intelligence, the majority of whose leaders might have been assets of the CIA. These two organizations have been collaborated, which is actually not a secret.
The police intelligence has got much intel from the CIA, which is open to the public and written in many government papers. The police intelligence has also been supported by the CIA technologically, one of which is an electromagnetic wave.
As discussed, the CIA did not hand over this technology to the whole police department in Japan. It was provided to the covert team, which eventually toppled rivaling police rankers and even the premier. However, it was given so secretly that those opponents did not realize they used the electromagnetic technology.
The Japanese government did not realize a capacity of the electromagnetic wave still in 2000 when those leaders were hospitalized, but this technology was brought to the police intelligence at least in the 1980s.
The only plausible explanation is that this small circle has been a CIA asset, which is why they have got this capability unnoticeably. This small circle had expanded their power from the covert team through the police intelligence to the whole police organization. They could have relatively easily achieved this object due to the electromagnetic manipulation.
Generally speaking, the CIA prefers an individual who can speak English. If cannot, there is a large possibility that the specific agent rules a contact to their asset and the information might be manipulated eventually, which is why they prefer someone to make themselves understood in English.
In the Japanese police department, the most suitable target is an officer used to work abroad as a secretary at the embassy. Some of the director candidates are often sent to assume the first secretary at some point of their career, which is basically a position to contact with the foreign intelligence agent. They basically spend a few years at this position so that there is an enough time for the CIA to convert them as assets.
The Japanese police intelligence is apparently a spy organization, but they have no oversea espionage capability. There are many intelligence officers working at the embassy, who basically obtain the information from the local police or CIA. It essentially means their HUMINT capability is defined by how profoundly they can get intel from the CIA. Furthermore, they can be provided more information once becoming the CIA asset.
This is the reason why there is an assertion to create the international intelligence organization centered by those police intelligence careers, i.e, the majority of them are almost CIA assets.
If the organization was built in this way, they would have influenced more on the Japanese foreign policy. Their plan was being failed so far, but there is still a large risk that the Japanese government is more controlled by the foreign agent.