Greg Torode

Gare Loch on Scotland's North Atlantic Coast is a long way from the South China Sea. Yet, in the frigid depths of its outer reaches, events are unfolding that serve to illuminate several challenges facing China and East Asia. Recent British press reports describe upgraded Russian Akula-class submarines manoeuvring off Faslane, where Britain bases the ballistic missile submarines that form a key part of its nuclear deterrent.

Naval officers are warning that the Russians are trying to record the unique sound of the British subs' propellers - allowing them to be identified and tracked, neutralising their stealth. The reports invoke cold war imagery, describing Russian tactics not seen off the British coast in 25 years. 

But for this region, they speak to the future, not the past. They are a timely reminder of the dark arts of submarine warfare just as the People's Liberation Army's expanding submarine fleet is facing unprecedented scrutiny. As the stealth, endurance and capabilities of China's submarines improve, PLA commanders can be expected to attempt similar operations; these are, of course, exactly what submarines do. That might mean adding steel to the rhetoric demanding the United States stop routinely exercising on China's coastal fringe, or quietly securing the Indian Ocean sea lanes, which will be increasingly important to China's oil-dependent future.

But as they do, they will face a uniquely Chinese challenge. Beijing's increasingly strident objections to long-standing US naval operations in East Asia may reflect the aspirations and confidence of a rising power but, strangely, they may also serve to limit China's future options. In short, China is almost certainly going to want to do the things it is now objecting to.

Its warnings to the US in the South China and Yellow seas go beyond activities within its 12-nautical-mile territorial waters and into its claimed exclusive economic zone. Yet the United Nations Law of the Sea - ratified by China - clearly allows a wide range of routine military activities by foreign nations within that zone. And surveillance, repeatedly objected to by Beijing, is considered a routine military activity.

To that end, US and Soviet ships of various types spent long periods of the cold war off each other's coasts without creating diplomatic storms. Submarines also penetrated territorial waters on a "just don't get caught" basis. The undersea cat-and-mouse games now under way off Scotland are a reminder of the way large military nations routinely exploit the international conventions that keep the oceans largely free.

If China had no intention of ever sending its own naval and surveillance vessels beyond its territorial waters, then its rhetoric would make slightly more sense. That, however, is not the case: the PLA is certain to be increasingly deployed across the Western Pacific and beyond. Surveillance ships have already been spotted off the strategic US islands of Hawaii and Guam, the increasingly important US naval base that forms a key link in the so-called second island chain that hems China in; PLA submarines have also repeatedly been tracked close to the Japanese coast.

"I can understand that the PLA is feeling strong and confident and wanting to exercise that new-found clout," said one Pentagon official recently. "I can understand that they've never liked the fact that, through its allies, the US is the dominant military power in East Asia ? but what I scratch my head about is how they seem to object to things that increasingly they will need to do themselves. We just don't get it."

It is a mystery that looks set to persist for some time yet. Back in June, General Ma Xiaotian , the deputy chief of the PLA's general staff, listed US surveillance in the South and East China seas as an obstacle to the resumption of fledgling military exchanges. Since then, the PLA has launched its own exercises to counter US-South Korean exercises in the Yellow Sea - something that, just a few years ago, would have been considered routine. At this point, it seems, tensions can only rise.

Greg Torode is the Post's chief Asia correspondent