President Xi is obviously not happy about what’s going on in the country that he’s accustomed to ruling with an iron fist. “Something is rotten in the state of Denmark,” the American ambassador to Japan, Rahm Emanuel, tweeted, borrowing an old Shakespearean line.

For sure Mr. Xi is unhappy, while China writhes in economic duress, but is he scapegoating some of the highest ranking figures around him?

Whether they’re living in quiet retirement or suffering grueling investigations and unspecified punishment is not clear, but Mr. Xi’s defense minister, or perhaps former defense minister, has been MIA — missing in action — for two weeks now, and seemingly no one has a clue where he is or how he’s doing. 

The disappearance of Li Shangfu, a general who previously commanded China’s manned space exploration program, is all the more shocking since he’d met President Putin and Russia’s defense minister, Sergei Shoigu, at Moscow in April and was due for sensitive talks with Vietnamese officials when he vanished.

The purge, if that’s what it is, evokes memories of the removal of Mr. Xi’s predecessor, Hu Jintao, last October from a meeting of the congress of the Chinese Communist Party, which he had led as general secretary for a decade until 2012. Was Mr. Xi humiliating him — or was he ill? Mr. Hu, 79, surfaced a few weeks later, but speculation goes on about why he was escorted out under the eyes of state TV.

Adding to the mystery of Mr. Li’s disappearance, Chinese officials profess ignorance about him. “I’m not aware of the situation,” was the latest response from a foreign ministry spokesperson. The foreign ministry is equally in the dark about the former foreign minister, Qin Gang, who was stripped of his position in July.  

Formerly ambassador to Washington, Mr. Qin had been the minister for seven months when he was unceremoniously dumped in favor of the man who had held the post previously, Wang Yi. As director of foreign affairs for the central committee of the Chinese Communist Party,  Mr. Wang took over the ministry in a shift not explained simply by the need for a tougher hand in the job.

Three factors, however, may account for the shake-ups in the two ministerial-level positions that have most to do with relations with foreign countries. The first one is health. There’s no evidence, however, that either Mr. Qin, 57, or Mr. Li, 65, suffered from disease or injury. Neither was too old to serve as a minister.

The whiff of corruption hangs over both these men, particularly Mr. Li, whose posts over the years may have provided opportunities for reaping hidden riches. The dismissal of two generals in the rocket force adds to suspicions that he was skimming from acquisition of equipment, but so far the Chinese aren’t saying.

Adding to suspicions is that Mr. Xi has been trying to stamp out corruption from the ranks of the world’s biggest military establishment, comprising 2 million troops in all services, while telling the armed forces to “comprehensively strengthen military training in preparation for war” — against whom, he didn’t say.

Could it be that Mr. Xi wants new blood, new leadership as he stages intimidation exercises in the skies and waters near the Republic of China on Taiwan, which he vows to recover? And is he concerned about border tensions with India and in the South China Sea, which China claims as its own  territory?

Mr. Qin is another case. A former chief spokesman for the foreign ministry, he served as ambassador to America for one year and five months before his elevation to foreign minister.

His dismissal was humiliating. His name deleted from official listings, he was cast into oblivion. What had he done to upset Mr. Xi? We don’t know. Mr. Li’s fate may be similar. Mr. Emanuel at Tokyo speculates he is under house arrest.

As Mr. Xi purges those he doesn’t want around, Mr. Emanuel tweeted, “Might be getting crowded in there.” If the purge goes on, he added, “Agatha Christie’s novel, ‘And then there were none,’” might be the way to describe the ranks around Mr. Xi.