Last week, a South Korean government agency provided statistical data regarding North Korea, some of which have great security implications. Among them were figures indicating North Korea’s rapidly expanding reliance on China for its external trade.

According to a report from Statistics Korea, North Korea’s volume of external trade was at a miniscule $5,093 million in 2009. It was nowhere near that of South Korea, which was posted at $686.6 billion.

China cast a long shadow on North Korea here, though. North Korea’s trade with China accounted for 52.6 percent of the total. It was the first time for its trade with China to surpass the 50 percent mark. In 2005, it accounted for 38.9 percent of the total.

North Korea’s trade with South Korea was at $1,679 million in 2009, or 33 percent of the total. But it is assumed to have drastically declined since North Korea’s torpedo attack on a South Korean naval vessel in March last year, pushing up North Korea’s reliance on China to a new height, which a Pyongyang watcher believes will exceed 60 percent this year.

China has been the chief food supplier for North Korea, a country with a chronic shortage of food, and, according to one estimate, accounted for 90 percent of its energy needs. Moreover, China is a main donor country for the North, with South Korea having halted an annual shipment of 300,000 tons of rice in aid for several years.

Given its trade with and aid for North Korea, China is seen to outsiders to have a stranglehold on its communist ally. But it says its influence on North Korea is not as great as it may look. Maybe so.

Still, if there is any country in the world that can rein in a wayward Pyongyang, it definitely is China. As such, South Korea and the United States are urging China to help stop North Korea from developing nuclear weapons and launching unprovoked acts of hostility against the South.

But the entreaty falls on deaf ears. China has been protecting North Korea from being chastised in the international community. Such an unlikely action raises so many questions regarding the underlying intention.

Is Beijing throwing its weight behind North Korea as a means of reasserting itself on the Korean Peninsula, as it is doing so elsewhere, in the context of confrontation between China and North Korea on one side and the United States and South Korea on the other? Does it mean that it has abandoned its long pursuit of legitimate expansion as a benevolent hegemon, pushing South Korea to consider a hitherto unthinkable alternative ― a defense alliance with Japan? If so, will it serve China’s interests better?

Moreover, a South Korean daily quoted Japan’s foreign minister as desiring a security alliance with South Korea, though it was denied by the Japanese Foreign Ministry later.

Another piece of information on North Korea that had security implications was about the widening gap between its gross domestic product and that of South Korea. Measured by the South Korean currency, North Korea’s GDP was at 24 trillion won, compared with 1,063 trillion won here.

The disparity implies South Korea is capable of massive aid to the North should it renounce armed provocations. But it made a grave mistake when it bit the hand that fed it in March and again in November.

The GDP gap also implies the North is no match for the South when it comes to spending on conventional arms. Though it frequently threatens to turn Seoul into a “sea of fire” ― the capital placed within the range of the North’s artillery across the Demilitarized Zone ― South Korea’s firepower should be strong enough to smash the North in the event of an all-out war.