(CNN) -- North Korea, under its untested young leader Kim Jong Un, has ratcheted up the threats toward South Korea and the United States to unprecedented levels and with greater intensity than ever before. A torrent of threats has flowed from North Korean spokesmen, including a promise of preemptive nuclear strikes on the United States and calls to "break the waists of the crazy enemies, totally cut their windpipes and thus clearly show them what a real war is like." North Korean brinkmanship, bluff, and bluster are stock elements in its diplomatic toolkit, but why have the threats become so outsized, and how worried should we be? Is North Korea playing the same game it has always played, or does the now-nuclear playbook of a rash young leader represent a new threat the we cannot afford to ignore?
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Scott Snyder: Kim Jong Un ratchets up threats toward South Korea and U.S. to record level
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Snyder: Bluff, followed by "charm offensive," is typical strategy but Kim gets closer to brink
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We don't know what Kim is trying to prove, Snyder says, or what political events drive him
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Snyder: South Korea and U.S. are tired of chest-thumping and it's not working anymore
Moreover, no one can be sure whether internal political challenges or a need to consolidate political control are driving young @placeholder to walk even closer to the edge than usual.