What are China's motives in South China Sea?

MANILA, Philippines — Why China keeps growing its presence and fueling the longstanding friction over the South China Sea is one lingering question that the United States and foreign policy analysts are trying to answer.

In its report to the US Congress about China's military, the Pentagon noted China's lack of transparency about its growing forces and strategic decision-making, most notably, over its assertiveness in the disputed waters claimed in part by the Philippines, Vietnam, Brunei, Malaysia and Taiwan.

Senior Chinese officials as well as official statements from Xi Jinping's government aim to project an image of a peaceful, emerging China, while its behavior in the waters has been called "forceful," "coercive," "intimidating," and most recently "destabilizing" by the United States.

Beijing's seemingly contradicting methods and statements in carrying out its foreign policy have raised concerns in the region, American Defense Secretary Chuck Hagel's office said.

"Absent greater transparency from China and a change in its behavior, these concerns will likely intensify as the [People's Liberation Army's] military modernization and program progresses," the Pentagon report said.

While it is clear the East and South China Seas are considered among China's "core interests," the deployment, testing and movement of military forces to pursue these interests are, for the Pentagon, "the most concerning aspects of indications and warning."

This is despite Chinese assertions that the staggering expansion of its military and maritime surveillance capabilities is mainly "defensive."

"It is unclear how China views the potentially escalatory nature of force posture," the Pentagon report added.

All about power

Robert Sutter, professor of International Affairs in George Washington University, said that China wants to consolidate its territory as a banner for the ruling communist party, whose legitimacy is being challenged domestically.

Prof. Robert Sutter speaks about the United States' role in the South China Sea dispute at a forum in the University of the Philippines on June 9, 2014.

In a forum at the University of the Philippines on Monday, Sutter argued that it is not the need to secure food and energy for its billion-strong population that makes China want to control the potentially oil-rich maritime areas.

"Is it an issue of survival than grabbing power? I don't think that's the driving force. This is ideology, this is nationalism, and this puts the issue [of maritime soveignty] at the very top of priorities of the Chinese government," Sutter said.

He explained that China is prepared to undertake tremendous costs to deal with any challenge posted against its sea claims.

The Chinese state can also aggressively pursue its sweeping claims over the sea simply because it can.

"What makes the Chinese do this? I say it's capability," Sutter said.

"They can do what they did in Scarborough (Panatag) Shoal and Second Thomas (Ayungin) Shoal. If they have capabilities, they're gonna use them. They can assert themselves," he added.

China also believes the maritime features and the waters are rightfully its own, despite its ambiguous "nine-dashed line" claim and even when the international court will rule against it.

"They think it's right. 'It's our territory we can do anything we want.' In a sense, they have contempt for the countries in the southeast," Sutter explained.

China has always expressed that the Philippines or Vietnam was the one provoking heightened tension in the waters.

Despite protests lodged by the Philippines, China successfully controlled Mischief (Panganiban) Reef in 1995 when it started building structures on the area off the western coast of Palawan Island.

Recently, Philippine defense officials bared China's reclamation efforts on various parts of the West Philippine Sea, protests against which China ignored.

Challenging the US

Bonnie Glaser of the Council of Foreign Relations believes that China may be counterbalancing against the US and competing with the Western power for influence in the region.

In this February 11, 2013 photo, the US Navy destroyer USS Stockdale crosses the South China Sea.US Navy/David Hooper

While China says it supports the US' interest of maintaining freedom of navigation in South China Sea, it insists that foreign militaries should seek permission while operating within its exclusive economic zone.

"China's development of capabilities to deny American naval access to those waters in a conflict provides evidence of possible Chinese intentions to block freedom of navigation in specific contingencies," Glaser said in a paper on the possibilities of an armed clash in the South China Sea released in 2012.

The US, meanwhile, has made a strategic "pivot" from Middle East to Asia Pacific in an effort to assert its leadership and interests in the region.