China enhances fleet of modern submarines;

China enhances fleet of modern submarines;
Rapid and secretive work troubles U.S.
For a procession of senior U.S. military commanders who have visited
China in recent years, the complaint has become almost routine.
As part of a sustained military buildup, they say, China is investing
heavily in so-called area-denial weapons without explaining why it
needs them.The term area-denial weapons refers to a combination of armaments,technology and tactics that could be used to dominate a specific areaor keep opposing forces at bay in a conflict. And one of the mostformidable examples U.S. commanders identify is the Chinese Navy'srapidly expanding fleet of nuclear and conventional submarines.
''I would say that the U.S. feels a strong threat from Chinese
submarines,'' said Andrei Chang, an expert on Chinese and Taiwan
military forces and editor in chief of the magazine Kanwa Defence
Review.''China now has more submarines than Russia, and the speed they are building them is amazing,'' Chang said.
U.S. and other Western military analysts estimate that China now has
more than 30 advanced and increasingly stealthy submarines, along with
dozens of older, obsolete types. ''China is capable of serial
production of modern diesel-electric submarines and is moving forward
with new nuclear submarines,'' the Pentagon said last year in its
annual report on the Chinese military.
By the end of the decade, experts say, China will have more submarines
than the United States, although it will still lag in overall
capability.

In a conflict, these Chinese submarines - many armed with state-of-the-
art torpedoes and anti-ship missiles - would sharply increase the
threat to enemy warships approaching the strategically important
waterways of North Asia, according to security experts.

On a visit to China last month, the senior U.S. military commander in
Asia, Admiral Timothy Keating, said the Pentagon was continuing to
monitor the development of China's area-denial weapons, including
submarines.

''Chinese submarines have very impressive capabilities, and their
numbers are increasing,'' Keating told reporters in Beijing. Like
other U.S. commanders, he also called on China to be more open about
its plans.

If China were more transparent about the need for these weapons, it
would improve trust and reduce the danger of crisis or conflict,
Keating said.

''In submarine operations in particular, because of the medium in
which they are conducted, underwater, there is greater potential, in
my opinion, for inadvertent activity that could be misconstrued or
misunderstood,'' he told reporters.

Under pressure from Washington, senior Chinese officers have said that
the buildup is strictly tailored to defending China's interests and
that it poses no threat to any other nation.

''The distance between the Chinese and U.S. militaries is big,'' said
General Chen Bingde, chief of general staff in Beijing of the People's
Liberation Army. ''If you fear China's military buildup, you don't
have much courage.''

While the administration of President George W. Bush continues to
press Beijing for transparency, most foreign security experts,
including senior Pentagon analysts, believe China's unstated
objectives are relatively clear.

They say that China plans to use its submarines and other area-denial
weapons to delay or deter a U.S. intervention in case of conflict over
Taiwan. China regards the self-governing island as part of its
territory and has warned regularly that it would use force to prevent
Taiwan from moving toward formal independence.

Stealthy submarines would pose a direct threat to the deployment of
U.S. aircraft carrier battle groups, almost certainly the first line
of any American response to a Taiwan crisis, according to security
experts.

In conjunction with attacks on military surveillance satellites,
regional U.S. bases and communication networks, the Chinese military
would attempt to keep U.S. forces at a distance while attempting to
overwhelm the island's defenses, they say.

''This is precisely what the submarines are for,'' said Allan Behm, a
security analyst in Canberra and a former senior Australian Defense
Department official. ''They can bottle up and deny an enemy access to
any given area; in this case that means the U.S. Pacific fleet.''

On previous occasions of high tension over Taiwan, Washington has
deployed aircraft carriers to neighboring waters, sending a signal to
China that it should not use force against Taiwan.

But in a clear demonstration of the increasing vulnerability of these
warships, one of China's new Song-class conventional submarines was
able to remain undetected as it shadowed the U.S. carrier Kitty Hawk
off the coast of Okinawa, Japan, in late 2006. It then surfaced well
within torpedo range.

For some China experts in the U.S. military, this was an aggressive
signal to Washington that ranked with China's destruction in January
2007 of one of its own obsolete weather satellites with an
antisatellite missile. In so doing, the Chinese Navy demonstrated that
it could challenge the most powerful surface combatants of the U.S.
Navy in waters around Taiwan. It also gave evidence that Chinese
submarine technology had advanced more rapidly than some experts had
expected.

''The U.S. had no idea it was there,'' said Behm. ''This is the great
capability of very quiet, conventional submarines.''

Submarine construction is clearly a top priority for the Chinese Navy,
and foreign analysts have noted that in recent years it has
concurrently developed four - possibly five - classes of new, locally
designed and built submarines.

Some experts have suggested that China is taking the same path as
Germany and Japan, which once relied heavily on submarines in a bid to
compete with the British and U.S. navies.

The attraction of submarines, the experts say, is that they are
extremely cost-effective weapons compared with surface warships. For a
relatively modest investment, stealthy submarines can threaten much
more valuable military and cargo vessels and attack targets on land
with missiles.

The suspicion alone that a submarine may be in the area can force an
adversary to operate more cautiously, while diverting resources to
expensive and complex detection and tracking.

In further evidence of progress in submarine technology, China
displayed photographs and models of its new Shang-class nuclear-
powered attack submarine at a Beijing exhibition in July celebrating
the 80th anniversary of the People's Liberation Army. The official
People's Daily newspaper reported that two submarines of this class
are now in service.

In October, Hans Kristensen, a nuclear weapons researcher with the
Federation of American Scientists, spotted on a Google Earth satellite
image what appeared to be two of China's Jin-class nuclear powered
ballistic missile submarines. Some military analysts were surprised
that China had built another submarine of this class so soon after the
first, in 2004.

And to put the improvement of its fleet on a fast track, China has
also taken delivery of 12 advanced Kilo-class conventional submarines
from Russia. These submarines are among the quietest and most
difficult to detect, according to veteran submariners.

Experts say the designs of the newest Chinese submarines show evidence
of technical assistance from Russia.

Analysts have also suggested that some of China's conventional
submarines have been fitted with so-called air-independent propulsion
systems. This would allow the submarines to patrol for extended
periods under water without needing to draw in air for the diesel
engines used to charge their batteries.

A number of naval experts have noticed that the growth in China's
submarine power has occurred while U.S. anti-submarine warfare
capability has declined from its peak during the Cold War.

What is more, in case of conflict over Taiwan, Chinese submarines
would have the advantage of operating in a favorable environment for
undersea warfare.

The waters of the East China Sea, South China Sea and Yellow Sea are
of uneven depth, with considerable background noise, complex thermal
behavior and strong currents. These factors make it very difficult, if
not impossible, for surface ships and aircraft to detect stealthy
submarines, even with the most advanced passive sonar and other
sensors.