Photo/IllutrationKomeito leader Natsuo Yamaguchi responds to questions from reporters in the prime minister’s office in Tokyo after a meeting between the government and ruling parties on Sept. 2. (Takeshi Iwashita)

Natsuo Yamaguchi on Sept. 8 marked 10 years as head of junior coalition partner Komeito, during which time he has walked a fine line trying to adhere to his party's peace principles while being allied with hawkish Prime Minister Shinzo Abe's Liberal Democratic Party.

Yamaguchi's tenure also brought stability to the coalition government, but it came at a price.

Votes gathered by Komeito in proportional representation segments of recent national elections are on a downward trend.

The challenge now facing Yamaguchi, 67, is to rebuild the power of his party.

Recalling his 10 years as head of Komeito, Yamaguchi told reporters: “I have made various efforts to maintain the (coalition) government. The (coalition) government and (the status of) a ruling party are the results of our unified efforts.”

He made the remark after meeting with Abe, also the LDP president, in the prime minister’s office in Tokyo on Sept. 6.

Komeito, along with the LDP, found themselves out of favor with the electorate in the 2009 Lower House election and in the position of being opposition parties.

Then Komeito leader Akihiro Ota failed to win a seat in that election, which led to Yamaguchi assuming the party's top post.

After the LDP and Komeito returned to ruling coalition status again in late 2012, Komeito championed an 8 percent tax on foodstuffs when the consumption tax rate is increased to 10 percent in October.

But it hasn't been plain sailing. Among members of Komeito’s core support organization Soka Gakkai, opposition was strong to proposed national security legislation and an integrated resorts implementation law to lift a ban on casinos.

But Komeito, along with the LDP, railroaded the related bills through the Diet, triggering a backlash in Soka Gakkai against Komeito.

This may partly explain the downward trend in votes garnered by Komeito in proportional representation segments of recent national elections.

It won more than one million fewer votes in the proportional representation segment of the July 21 Upper House election than it gained in the Upper House election held in 2016.

Abe has made clear his determination to proceed with discussions on constitutional revisions in or after this autumn.

However, Yamaguchi is cautious about the LDP’s insistence of clarifying the legal status of the Self-Defense Forces in pacifist Article 9 of the Constitution. This will likely lead to some sort of confrontation with the LDP over the issue.

Yamaguchi’s tenure as head of Komeito renews the longest record since the party was re-established in 1998.

Land minister Keiichi Ishii, who is expected to leave the post in a Cabinet reshuffle to be held Sept. 11, is tipped to become Yamaguchi's successor.