Christian Whiton is the president of the Hamilton Foundation and the author of " Smart Power: Between Diplomacy and War ." He was the deputy special envoy for human rights in North Korea during the George W. Bush administration. The views expressed are his own.

In an unsubtle lesson, hundreds of people were required to watch as Hyon Yong-Chol was apparently obliterated by an anti-aircraft gun. Being a top official in North Korea, it seems, has become increasingly dangerous.

The recently departed defense minister began his climb to high office not long after Kim had Jang Song Thaek, his uncle and the man widely seen as a tutor and unofficial regent to the young leader, frog marched out of a formal assembly in December 2013. He was later killed , according to an announcement by state media, possibly also by exotic means. Several other officials were purged as well.

Such events are unusual even for North Korea -- while political dissent at any level is met with the harshest of punishments, seldom have so many senior officials been purged in successive waves.

So what exactly is behind these moves?

It goes without saying that deciphering what is really going on in North Korea is extremely difficult -- it is run by one of the most repressive regimes on Earth. Still, some analysts believe the recent activity suggests Kim is in a precarious position. The thinking goes that Kim is deeply fearful that his rule could be challenged, and thus is willing to kill anyone he sees as a potential rival. A sense of insecurity about his position may also explain the recent cancellation of Kim's planned trip to Moscow for Russia's celebration of the 70th anniversary of V-E Day -- Kim had been scheduled to attend last week, but canceled due to what Russian officials described as "internal Korean affairs".

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But precariousness and insecurity are two different things. While no one on the outside really knows, there are signs that the Kim regime is actually stable. Rapidly expanding trade with China in recent years has helped the economy. (Beijing often says it is fed up with Pyongyang, but its actions tell a different story.) North Korea reportedly now has as many as 20 nuclear weapons and the ability to strike North America directly. It recently tested its first submarine-launched ballistic missile. State propaganda casts Kim as a beloved figure jovially dispensing military, industrial, and social guidance to a degree that equals or exceeds his father's and grandfather's cults of personality.

Some of this suggests that contrary to the image of a panicky, unsure, inexperienced boy dictator, Kim may be perfectly in his element as an effective tyrant. Furthermore, those who hope Kim's purges will inspire North Korean officials who fear that they could be next on the chopping block to eliminate Kim, may be disappointed. One need only examine the reigns of Joseph Stalin and Mao Tse-tung to see that those most apt to murder their colleagues can also be the most durable and seldom challenged.

Where does this leave U.S. policy toward North Korea? Administrations of both political parties have wavered between intense negotiations that ended up appeasing North Korea and periods of inaction that amount to little more than hoping for the best. The result is a North Korea that has grown in a decade from an exotic regional nuisance to a more direct and significant threat -- one that is led by a young dictator who looks less buffoonish and more diabolical by the month.

If policy doesn't change, this trend of increasing danger probably won't either. Until the United States and its allies challenge the regime and its enablers more directly and effectively, the threat will persist. And it may very well worsen.