China and Japan, along with North and South Korean troops at the DMZ, appear one step away from armed combat and tensions don't look likely to ease any time soon.
New developments within both regions illustrate how close to open combat the four countries are, and how quickly one incident could expand to war among very powerful nations.
Tokyo reported two January events where Chinese naval vessels targeted its East China Sea forces with fire-control radar. This specific type of radar is used almost exclusively to assist guided weapons systems in their flight toward a target. It's an unmistakable action that can be the first step to open combat, and was taken seriously enough by the Japanese captain to prompt a combat alert aboard his vessel.
The Chinese Foreign Ministry responded to the allegations by saying it hadn't heard about the engagements until news of the events appeared on international news. It has since said that the event didn't happen and is a total Japanese fabrication. Whether it's true or not China is using Japan's claim to prove Tokyo is preparing for war.
If Chinese ships did engage their fire-control radar, it may be in Beijing's interest to deny it because either it approved the maneuver, or the ship's captains acted independently. Both scenarios offer a long list of concerns that would be easiest for China to address if avoided entirely.
Japan continues pressing the issue and yesterday announced that the use of fire-control radar against its ships is an "act of force" and a direct UN charter violation."
U.S. Secretary of Defense Panetta is pleading for caution and says, "the situation could ultimately get out of hand."Not everyone believes fighting is inevitable, but it's perhaps just as likely as not.
Meanwhile along the most heavily-fortified and well-armed border in the world, South Korean troops on the border with the North have received orders to return fire immediately against DPRK forces.
Pyongyang three years ago shelled the South and Seoul's response time was harshly condemned. The new rules of engagement are intended to prevent the same thing from happening again
Reuters quotes a South Korean commander stationed on the border who says: "We will respond immediately to any enemy provocation." That Captain, along with every South 
Korean soldier stationed along the border, operates under this standing defense ministry order: "punish automatically ... until the enemy surrenders."
North Korea failed to surrender in the last war it fought with China against South Korean and U.S. forces, leaving little reason to believe it would do so today.
And as Pyongyang moves forward with its most recent nuclear test, there's no reason to think it wouldn't use that technology against enemy forces long before accepting the notion of defeat.
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