Japanese are disappearing in slow motion and so far, there is no rescue plan. Every January, those turning 20 over the next twelve months celebrate their Coming-of-Age Day at shrines across the nation. Yet each year there are fewer of them. This year, only 1.2 million youth will turn 20, half as many as in 1970.
On U.N. calculations, the 2010 population of 127 million will shrink by a fifth, to 101.6 million in 2050. Moreover, the decline speeds up over time, with the population dropping by 6.65% between 2015 and 2030, but plummeting a whopping 13.4% from 2030 to 2050—far and away the worst growth projection in the world. Consider that Pakistan is expected to nearly double its population, to 335 million, in the same period.
While the state plays at most an indirect role in childbearing, family planning does reflect broad social trends. In Japan, the whole demographic of pregnancy is changing. In 1970, the average age of women having their first child was 25.6; in 2007, that had jumped to 29.4. Even more dramatically, in 1970, half of all babies were to women in their mid- to late-twenties; today, fully 38% of babies are born to women in their early thirties. This means that fewer women are willing or able to bear second and third children when they start so late.
This is partly due to the difference between how older generations lived in their twenties and thirties and the lifestyle of the youth today. The average age of marriage is steadily increasing, up to 28.3 for women and 30.1 for men. This has led to an entire generation of women marrying later, if at all. In the early 1970s, over 1 million couples wed annually—300,000 fewer couples marry today.
At both ends of the demographic spectrum, single-person households are increasing rapidly in Japan, from just 600,000 in 1975 to over 4 million today, with the majority of these households being single, elderly women. Youngsters who remain unmarried are called "parasite singles," often living at home with their aging parents.
That there are so many single, elderly households in Japan is due to the fact that it has the world's longest life expectancy, thus compounding the fall in birth rates. Japanese women currently have a life expectancy of 86 years—this is expected to rise to a record-shattering 91 years by 2050; men are expected to live to 83.5 years by the same date. Moreover, by 2050, nearly 40 percent of the population will be aged 65 years or older.
Japanese society can hardly claim to be taken by surprise by these trends. It takes decades for a drop in fertility rates to become a decrease in population. Indeed, the country's birth rate actually fell below replacement rate in the early 1970s.
There is no parallel in modern times for the population drop Japan will soon face. There is no way to accurately predict what this will do to its ability to grow food, maintain its industrial base or defend itself. On the positive side, it is conceivable that a burst of innovation and automation globally may help counter Japan's future demographic challenges. Dystopian visions of robots running more of society may become a reality.
Policy makers have failed to adequately prepare. Most other societies would make up the demographic shortfall by encouraging immigration. Yet Japan has negligible legal immigration, due in part to onerous laws. Unregistered immigrants abound from China, North Korea, Southeast Asia and the Middle East. These less-skilled laborers work in industries such as construction and service industry. But they do not stay for long term, speak the language or assimilate even moderately into society.
The problem is that many Japanese do not want to see Western-style immigration, fearing that their culture will be irrevocably changed should non-Japanese get a foothold in society. Instead Japan uses immigrants as temporary workers, and forgoes the benefits of integrating them into educational, economic or political life.
The core issue of how the nation will continue to prosper with ever fewer citizens is just not under consideration. A national debate on the matter is the need of the hour. If they don't want to change their attitude to immigration, they should realize that they will have to change their lifestyle—and allocate resources to helping the elderly, or building more robots. Chances are, once they understand what's at stake, many Japanese will open up to the alternative: allowing more people in.
Conservative Japanese will no doubt bring up the matter of culture. A national identity crisis will be familiar to those in many western European countries with high immigration rates, but Japan's homogeneous society has so far avoided dealing with these questions. Given current trends, it may not have the luxury of time to decide how it wants to keep its culture intact if its society is shrinking.
Mr. Auslin is the director of Japan Studies at the American Enterprise Institute and a columnist for WSJ.com.