TOKYO (Reuters) - As a Japanese military recruiter sat patiently at a booth outside a supermarket in northern Tokyo one recent weekend, she welcomed a rare visitor, high school student Kazuaki Matsumura.

Japanese Ground Self-Defense Force members take part in an annual training session near Mount Fuji at Higashifuji training field in Gotemba, Japan August 23, 2018. REUTERS/Kim Kyung-Hoon

But Matsumura, who plans to go to university, wasn’t there to sign up. He was just curious.

“There are scenes in the media that spark interest in the Self-Defence Forces,” the 16-year-old said, referring to Japan’s military. “But there are also scenes showing how tough it is and I don’t think many want to join. They want to do other things.”

Empty recruiting tables and disinterested audiences are becoming more common for the SDF as Japan’s demographic troubles and robust economy have created what some defense insiders call a “silent crisis” for military recruiting.

Amid a rock-bottom birth rate, the number of Japanese age 18 to 26 - the core of the recruitment pool - has shrunk to 11 million from 17 million in 1994. That group is forecast to shrink to 7.8 million over the next 30 years.

That has left the SDF unable to hit recruitment quotas since 2014. Overall, the military was only able to recruit about 77 percent of the 9,734 lowest-rank enlisted personnel it had sought in the year ending in March.

“Twenty years from now, unless we can replace a considerable number of people with robots, it’ll be hard to maintain the current level of war capability,” said Akihisa Nagashima, a former parliamentary vice defense minister and conservative independent lawmaker. “Japan’s (security) situation won’t be more peaceful, so I think this is really serious.”

The personnel crunch could force Japan’s military into tough choices about future missions as it tries to contain China’s maritime expansion and deal with volatility on the Korean peninsula.

“The manpower shortage will affect operational efficiency,” said Hideshi Tokuchi, a former vice defense minister who once headed the ministry’s personnel bureau. “It is a headache. There is more to do with fewer people and I don’t think there is any easy solution.”

A TOUGH SELL

As Japan’s economy has improved, unemployment has fallen to around a 25-year low. More high school grads are also heading to college.

That is good news for the country, but it makes military recruiting even tougher.

“Even though we have the budget, we fall below the allotted number of troops,” said Kenji Wakamiya, a former defense vice minister who heads a ruling party panel on defense policy.

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Japan budgeted for 247,154 SDF personnel in the year to March 2018, but the military employed only 226,789. The biggest shortfall is in the lowest ranks of enlisted personnel, which were roughly 26 percent below their budgeted level.

With conscription deemed unconstitutional, the military is trying to recruit more women, and starting next month, the maximum age for new recruits will be raised to 32. Retirement ages may be increased as well.

“There was a time when it was thought youth equals strength, but if you think about it ... experience and skill have become even more important for today’s SDF,” said Ritsuko Hiroshi, director of the defense ministry’s personnel affairs division.

A Female Personnel Empowerment Initiative unveiled last year aims to double the percentage of women in the SDF from 6.1 percent in 2016, and to at least 9 percent by 2030.

That compares with about 15 percent in the United States and 10 percent in Britain.

Although Japanese women can hold a wider range of military jobs than they once could, they still are often assigned to non-combat roles, officials and experts said.

“They tend to be positions that are traditionally coded female ... anything that doesn’t require picking up a weapon,” said Sabine Fruhstuck, a professor at the University of California, Santa Barbara.

A SOFTER IMAGE

Recent pop culture campaigns such as manga-style posters help create a “soft” image of the SDF among the public, but the impact on recruitment is limited, experts said.

“Hardly anyone joins because he or she saw a poster. They are encouraged to join by parents or relatives or teachers who were former SDF members,” said Hitotsubashi University professor Fumika Sato, who researches recruitment.

It takes roughly 5,000 SDF officials, many in regional headquarters, to recruit about 14,000 new personnel each year.

“It’s a very time-consuming, labor-intensive business,” Tokuchi said. “Recruiters have to approach high schools and parents to explain what they have to do and can do in the military ... and then take kids to events organized by the defense forces and induce them to take the exam,” he said.

The defense ministry is seeking a 5.8 percent increase in the military recruitment budget for the year from April to 2.4 billion yen ($21 million).

The SDF last year embraced internet advertising, which resulted in a three-fold increase in visits to its recruiting homepage, said Major Yoshiaki Hayashida of the Ground Self-Defence Force staff office’s personnel division.

About 90 percent of the public has a positive view of the SDF, surveys show, largely due to military disaster relief work, but that doesn’t necessarily mean they want to serve, recruiters and experts said.

“People want to join because it’s challenging, a stable job and because they want to be useful,” said Colonel Shuzo Yoshida, head of recruiting at the SDF’s Tokyo Provincial Cooperation Headquarters.

Hiroki Hashimoto, 24, who attended an army technical high school and the National Defence Academy, was more explicit.

“Many people join the SDF or attend its technical high school because they are poor. That is a fact,” said Hashimoto, who did not enlist.

A post-war attachment to pacifist ideals also complicates recruitment.

“Compared to 10-20 years ago, the SDF is more firmly established in society,” Nagashima said. “But because Japan had the trauma of defeat in the war, and many were sacrificed, I think it will take 100 years (for sentiments to change).”

(This story corrects spelling of name of former vice defence minister in 12th paragraph to “Kenji Wakamiya” not “Kanji”)