A few months back, we reported here at D&D on the crisis surrounding artillery barrages fired by North and South Korean forces into the highly contested maritime zone along the Northern Limit Line (NLL) in the Western Sea.

That escalation has continued, though our coverage of it has not. I have been hesitant to speculate on the swirling crisis around the suspicious sinking of the South Korean Corvette Cheonan on March 26, that claimed the lives of 46 sailors.

I was hesitant, mainly because there was little more than speculation around the causality of the Cheonan's sinking. Tonight, it appears that our wait may be over.

Whispers have been leaking from the South Korean defense establishment all day today, as the South Korean navy raised the sunken half of the Cheonan from the bottom of the Western Sea -- looking for answers.

Yonhap news has begun publishing, and then removing, some of these whispers:

"It is the military intelligence's assessment that the North attacked with a heavy torpedo."

Chosun Ibo, a South Korean Daily, has run with the story.

The inference is that the North Koreans have made the first combat-effective use of their rumored suicide torpedo units. The units have been, to this point, mythic -- a boogie man brought out in the debriefings of high-value North Korean defectors, who describe a unit of 13 specially trained special forces members, and modified midget submarines. The Telegraph reports now that sources claim these men were responsible for the sinking of the Cheonan.


(more after the jump)

If true, the orders to strike the Cheonan came from the very top -- Kim Jong Il, who personally commands this special unit of suicide submariners. Riding modified Japanese Kaitans, these men may have given their lives to commit the bloodiest action since the cease fire between North and South in 1953.

The accusation, should it be born out by the investigation, will be send shockwaves through the region. The crisis in the Western Ocean along the NLL has been escalating for over a year now, with fire exchanged by both sides, and casualties taken in escalating numbers. While the 'long fuse' of North/South Korean tension has been rising since the cessation of hostilities, the actions along the NLL in the Western Ocean are escalating in frequency and seriousness.

It started last March, with North Korea's declaration for a No Sail-No Fly zone along the NLL. A month later, a South Korean Naval Patrol opened fire on a North Korean vessel that had crossed the NLL. Six days later, the South was forced to evacuate its naval assets from the region when they detected North Korean land to sea missile radars painting their ships.

Both sides have been moving land-based and sea based assets into the region. At first it appeared that North Korea intended to begin a new battery of missile tests in the region -- and wanted to keep inquisitive eyes clear of the region.

The North declared the NLL a "peacetime firing zone", unilaterally banned all commercial transit along the line -- east of the island of Baeknyeong and and west of the island of Daechyong, both locations of South Korean Naval and Marine Bases. One day later, they signalled their intent to enforce their declaration, and fired hundreds of artillery rounds into the zone.

If the Cheonan was sunk by a North Korean torpedo, it will stand as an escalatory fait accompli that South Korea will find very difficult to ignore, especially as domestic pressure rises in the South, and international pressure ramps up in the region.

My snap analysis back in March may still stand -- North Korea may still intend a new round of missile tests based near the NLL, especially as the joint Japanese-US SM3 missile defense programs are showing impressive progress. However, North Korea may have finally become too zealous in their escalatory tactics in the Western Sea.

Time will tell, but a crisis is brewing in an area where crises should not brew. The message is clear -- North Korea will respond to any perceived Southern naval dominance. The naval action of Nov. 10, 2009 was generally considered a victory for the South, and cost North Korea the life of at least one sailor. Their response?

Look for the headlines tomorrow.

For a closer look at the escalating crisis, see the time line below:

March 29, 2009 -- North Korea Declares 2 "No Sail/No Fly" Zones in the long-contested Western sea border between North and South Korea

November 10, 2009 -- A South Korean Patrol Ship opened fire on a North Korean naval vessel that had crossed the NLL (northern limit line), exchanging fire with that vessel, killing one North Korean sailor, wounding 3.

November 16, 2009 -- South Korea evacuates naval ships from the Western sea after detecting signs that North Korea had activated radar for surface to ship missiles deployed on the Ongjin Peninsula, Hwanghai Province, and had painted South Korean ships.

December 22, 2009 -- North Korea declared a "peacetime firing zone" along both sides of the NLL, to counter "the reckless military provocative manoeuvres by the warmongers in the South Korean military." warning of the deployment of both land based artillery and land to sea missiles.

January 25, 2010 -- North Korea unilaterally announced a shipping ban on both sides of the NLL, specifically in the region of east of the island of Baeknyeong and and west of the island of Daechyong, both locations of South Korean Naval and Marine Bases.

January 26, 2010 -- North Korea opened fire with land based artillery into the contested maritime border region, an action that was met with retaliatory "warning shots" fired by South Korean forces.

March 26, 2010 -- The Cheonan suffered a devastating explosion below the waterline, the explosion occurred away from ordinance storage, weapons systems, or fuel tanks.