There are a lot of other stories that have been in the forefront of the news in Japan this week. But there's another one that hasn't gotten the airtime it deserves – even though it might be the most important of all.

It's about Yuriko Koike, Japan's first female Defense Minister, who abruptly quit in August just weeks after her appointment to the job. At the time she was harshly criticized for the seemingly arbitrary actions that precipitated her departure. Yet now events have dramatically vindicated her move, in ways that suggest that her 55-day tenure may end up being remembered as a remarkable achievement. What did she do? Simple - she fired her deputy, the top-ranking civil servant Takemasa Moriya. The problem was that she didn't really explain it very well. All she said was that he'd been in his job for much too long (twice the regular two-year term). He was so entrenched, as a matter of fact, that people gave him the nickname "the Emperor." As soon as Koike made her announcement, the 62-year old veteran bureaucratic infighter immediately started a campaign of resistance, going so far as to petition Prime Minister Shinzo Abe. But Koike stuck to her guns. Moriya headed off into retirement, but soon his boss was also forced to leave office under circumstances that have never really been clear. On the surface of things her motives seemed flimsy. Though acknowledging that she had the legal power to decide his removal, critics muttered that she had somehow violated unwritten rules of political decorum. Some of the commentaries hinted that flighty females couldn't be trusted with matters of real importance. In any case, Japan's political classes soon moved on.