US-Chinese naval standoff the latest in a string of clashes

The US Navy has accused Chinese ships of harassing a US submarine-tracking vessel in the South China Sea.

BEIJING – Chinese fishermen nearly made off with some of the US Navy’s most modern and secret submarine tracking equipment, it seems, in a South China Sea incident Sunday that is making diplomatic waves.

Unarmed American seamen on the USNS Impeccable were reduced to turning their firehoses on five Chinese military and fishing vessels – one of which approached to within 25 feet before the US ship withdrew, according to the US Navy account.

The incident is the latest in a string of clashes and standoffs between Chinese and US military forces in the South China Sea, though with both Beijing and Washington apparently keen to maintain close relations, this affair is not expected to boil over.

Chinese Foreign Ministry spokesman Ma Zhaoxu Tuesday said the Impeccable “broke international and Chinese laws” and had deserved to be seen off.

The US Embassy here countered that the civilian-crewed US Navy ship had been “conducting routine operations … in accordance with customary international law.” A Pentagon statement accused the Chinese vessels of having “aggressively maneuvered in dangerously close proximity” to the Impeccable.

So what was going on last Sunday? Just a more public, and possibly more dangerous spat in the ongoing cat and mouse game that the US and Chinese navies play quietly all the time in the South China Sea.

There is little doubt what the Impeccable was doing 75 miles off the coast of the island of Hainan, where the Chinese have built a major submarine base. It is one of only four US ships worldwide equipped with the latest generation of sub-hunting sonar, known as SURTASS LFA (which stands for Surveillance Towed Array Sensor System - Low Frequency Active, in case you were wondering.)

At one point during the incident, “the Chinese used poles in an attempt to snag the Impeccable’s towed acoustic array sonars,” reported the US Navy’s press service, quoting Pentagon spokesman Bryan Whitman.

Had they succeeded, it would have been embarrassing, to say the least. In a 2007 environmental impact statement, the Navy described LFA as “the only available technology capable of meeting the US need to improve detection of quieter and hard-to-find foreign submarines at long range.”

With Hainan not far from Taiwan, the island-state that China claims and the US has pledged to defend against any attack, this is sensitive technology. The aircraft carrier USS Kitty Hawk was discomfited a couple of years ago when it was on maneuvers and a Chinese submarine surfaced a few hundred yards off its bow. None of the flagship’s carrier-strike group had spotted the intruder.

Sunday’s incident came after a week of what the Pentagon statement called “increasingly aggressive conduct by Chinese vessels” aimed at the Impeccable and a sister ship, including low-altitude flybys by Chinese maritime surveillance planes.

The Chinese appear to be stretching the law when they claim that the Impeccable was engaged in illegal activities. The UN Law of the Sea does not specifically permit military activities within other countries’ 200-mile "exclusive economic zones," but it only specifically prohibits them within 12-mile territorial waters, and nobody is saying the Impeccable was that close to the Chinese coast.

Oh, and why did the Navy have to produce an environmental impact report on the Low Frequency Active sonar? Because not only the Chinese are upset about it. Conservation groups in the US had charged that the system disturbs whales and other ocean-dwelling mammals. Their objections were overruled.