When Prime Minister Shinzo Abe declared that he intended to promote women in the workplace, many people were understandably skeptical. After all, Abe is known as a conservative, and conservatives in most countries support traditional gender roles. Perhaps for this reason, many writers rushed to declare that "womenomics" wasn't for real. But I believed that something big had changed in the Japanese mindset, and that this time really was different. I came away from a recent trip to Japan even more convinced that womenomics is a deep and permanent shift that will reverberate throughout the country's social and economic structure.

The first reason for my increased confidence is that I now understand the strongest force behind the push to hire women. It's not Abe — it's demography. The rapid decline of Japan's working-age population — down more than 11 percent from its mid-1990s peak, and still falling — has made companies desperate for talent. That means hiring either foreigners or women. Women, having no language barrier, requiring no visa sponsorship and being already well-acquainted with Japanese corporate culture, are the natural first choice. For many Japanese companies, therefore, hiring women isn't an act of social responsibility, gender fairness or capitulation to the government — it is a simple act of survival.

This makes Japan's gender revolution different from those of the U.S. and Europe, which put women to work back when the population was young and growing. In the U.S., increasing pressure for corporate profitability, resulting from globalization and the shareholder revolution, forced companies to hire the best available talent at the lowest available price — in many cases, that meant hiring women. In Europe, progressive governments added their weight to those natural economic forces. But in Japan, the economic pressure comes from demography rather than profitability, and the government is worried about the Chinese threat rather than social equality.