The latest chapter in lessons of Kim Jong-un's saber-rattling has left us with this: South Korea and U.S. are pretty convinced North Korea isn't that serious about making good on its bellicose threats of war — the propaganda-happy nation wouldn't even fire a potential first shot in any conflict. So why is the U.S. continuing its own show of force by moving a big ole missile destroyer and a mobile-radar station in the direction of North Korea?

"The U.S. Navy is moving at least one warship closer to the North Korean coastline and more may be on the way," CNN's Barbara Starr reported Monday afternoon, adding: "The SBX-1 radar, a sea-based platform with a radar on top, is also on the move." That warship appears to be the USS Fitzgerald, which is being moved to the waters beyond the Korean peninsula. "The USS Fitzgerald is capable of intercepting and destroying a missile, should North Korea decide to fire one off," reports NBC News, which adds that it is "unclear if the Fitzgerald was also part of the ongoing military drills."

The SBX-1 seems like another defensive safety precaution. Here's a quick description of from Naval-Technology.com: 

The platform was developed by Boeing, as part of the ground-based midcourse defence (GMD) component of the US Ballistic Missile Defence System (BMDS). The GMD intercepts incoming warheads.

Yes, that's the word "warhead" in that description. (And, no, this has nothing to do with the sequester.) The mobilization of warships doesn't exactly seem to jibe what we've been told of late — that North Korea is puffing its chest up and is largely bluffing about its threats. But the mobilization of warships does match up with the passive-aggressive show of force from the U.S. military, which flew nuclear-capable stealth B-2 bombers over South Korea for the first time in history on Friday to send a message, then flew two F-22 Raptors over South Korea as part of a military exercise on Sunday. 

Still, this sounds more like the naval war games following Iranian tough talk last summer, and U.S. officials have suggested that all these planes and ships and deterrents are more of a show of force in reaction to fighting words from the East. "We have no indications at this point that it's anything more than warmongering rhetoric," a senior Washington Defense official told CNN late Friday, and the National Security Council followed up by saying, "we would also note that North Korea has a long history of bellicose rhetoric and threats, and today's announcement follows that familiar pattern." And even though North Korea's month of upping-the-ante rhetoric has culminated of late in the rogue nation saying this weekend that it's back in a "state of war" with South Korea and that the "final warning" has come, Chinese news blog China Smack notes that South Koreans believe Kim Jong-un would not fire the first shot of any potential conflict:

According to leaks by multiple South Korean intelligence personnel on March 31st, although Kim Jong-eun made many high-profile inspections of the armed forces, he internally issued secret commands, ordering North Korean front-line military to maintain high alert and at the same time ensure that they do not fire the first shot. Kim Jong-un emphasized that they not create any opportunity for a “retaliatory strike” by South Korea and America.

So, long story short: North Korea is, like it always has, crying wolf about "breaking its enemies waists," and threatening to hit the "boiled pumpkin" that is the American mainland, nuclear "treasure" fantasy and all. The U.S. knows this, but we're bringing along some muscle just in case.