A report on Japan's "comprehensive security strategy" was drawn up by the Cabinet of Prime Minister Masayoshi Ohira in 1980.

In the report, a sentence says, "When we look back on the debate on national security, we have to admit that we were caught between two extreme arguments--one themed on military buildup aimed at self-defense and the other dedicated to arms abolition based on pacifism--and that we failed to nurture a national environment to think about the issue in a realistic manner."

But 44 years later, the "polarization" has deepened even more as it changes in form.

The most severe "division" can probably be found in the situation concerning Okinawa Prefecture.

With the security environment surrounding Japan growing more volatile, the government has substantially increased its defense budget to possess a counterstrike capability.

The U.S. military and Japan's Self-Defense Forces are proceeding with plans to reorganize their units stationed in the southernmost prefecture, the front line of security.

Meanwhile, the confrontation between the central and prefectural governments has become intensified over the planned relocation of U.S. Marine Corps Air Station Futenma in Ginowan in the prefecture to the Henoko district of Nago and other issues.

The central government resorted to administrative subrogation and approved the change necessary for the land reclamation plan without gaining the approval of the prefectural government, ignoring Okinawa's sentiment.

I visited Okinawa Prefecture in late February with students of my seminar at the University of Tokyo to see how the division should be viewed.

I wanted to listen to what locals had to say, and accept and think about the complex nature of the events as they were.

We visited the U.S. Kadena Air Base straddling Kadena and its neighboring municipalities, which will serve as the largest foothold for the U.S. Air Force in the event of a military contingency, and the Futenma base to receive explanations from senior officials about the roles of the bases and their perceptions of the security environment.

When we went up an elevated platform outside the Futenma air station overlooking the base, we met people who said they were at the ready with cameras at all times because it would be the first base to make the first response in the event of a contingency.

We also visited the Ground SDF's 15th Brigade, which is being considered to be upgraded to a division, as well as the Air SDF's Ninth Air Wing that scrambles fighter jets to intercept approaching Chinese aircraft and respond to other threats.

Meanwhile, we also went to the Himeyuri Peace Museum dedicated to female student nurses mobilized during the 1945 Battle of Okinawa and the Cornerstone of Peace memorial, which is inscribed with the names of war victims, to exchange opinions with senior members of a local newspaper and representatives from Voice of Okinawa and Ryukyu, a civic group protesting military bases.

They told us about the absurdity of Okinawa being home to the largest concentration of U.S. bases in Japan, while also expressing their resentment toward The Asahi Shimbun, other national papers and mainlanders for not paying due attention to Okinawans.

Responses from the students after the visit were varied.

While they gained a realistic sense of the security front line and expressed understanding for the need to reinforce deterrence, many of them said that they were shocked by how Okinawans felt so strongly negative about mainlanders and that they felt how deep-rooted the division was.

Okinawa was once known as the Ryukyu Kingdom for centuries. But the Meiji government (1868-1912) forcefully transformed it into the prefecture of Okinawa.

During the ferocious Battle of Okinawa against U.S. forces, Okinawa Prefecture was turned into a "breakwater" to delay an invasion into the main Japanese islands and was subjected to intensive air and naval bombardments.

And after the war, the prefecture was placed under U.S. military rule.

Given these historical circumstances, some pointed out that locals share a sense of crisis that Okinawa would be exploited and abandoned again in the event of a military contingency.

But how can we overcome the division?

Some said that the government's hard-line stance will cause a feeling of distrust even among generations who have no anti-U.S. sentiment and lead to a prolonged delay in resolving the issue.

They also said that the government's "public stance" of protecting human lives and its "real intention" of viewing Okinawa as a breakwater make it difficult to resolve the problem.

Others said the only way to quell the distrust of Okinawans is to review the Japan-U.S. Status of Forces Agreement, the root cause of their sense of unfairness.

With the central and Okinawan prefectural governments increasingly alienated from each other, I think it is problematic for the central government to take advantage of China's threat and drown out the opinions of Okinawans.

The division in society and politics can be used as a positive factor by a country to unsettle another.

Possibly detecting the division within Japan, Chinese President Xi Jinping said in June last year that there were "deep interactions" between China and the Ryukyu Kingdom in an apparent bid to curry favor with Okinawans.

The central government must be aware that if it encourages the division, it will definitely have repercussions for Japan's security.