Over the last decade, China has taken an increasingly muscular approach to relations with East Asian countries. But in recent months, it has surprised its neighbors with a charm offensive. What changed?

In terms of China's behavior in the region, quite a lot. In 2013, China declared an air defense identification zone covering the East China Sea's disputed Senkaku Islands — a move that exacerbated tensions with Japan. A year later, China began to construct large artificial islands in disputed areas of the South China Sea. In 2016, China imposed sanctions on South Korea in response to the decision to allow the United States to deploy a missile-defense system there.

Now, however, such geostrategic bullying seems to be taking a backseat to diplomacy. Last month, Chinese President Xi Jinping welcomed Prime Minister Shinzo Abe to Beijing. Abe's official visit to China was the first for a Japanese leader in seven years, and Xi's scheduled visit to Japan next year will be the first for a Chinese president in more than a decade.