India's stunning decision to unveil its nuclear weapons capabilities with this week's five underground test blasts may mark the beginning of a strategic rivalry with China for influence in Asia.
The world's two most populous states have improved relations in recent years. But they remain locked in a border feud that ignited a 1962 war, and India sees China as its greatest security threat.
Although Beijing has viewed the United States as its main strategic rival in the Asia-Pacific region, it has actively sought to contain New Delhi for years by providing conventional and - allegedly - nuclear weapons capabilities to Pakistan, India's foe in three wars since 1948.
But India's new nuclear might and its ongoing development of a missile that can reach most of Asia, including Beijing, will greatly enhance its ability to project military force far beyond its borders, increasing the potential for new tensions with China, experts say.
"The implication ... is that you are going to get a run for your money in terms of Asian leadership," asserts David Winterford, an expert on Asian security at the US Armed Forces Staff College, in Norfolk, Va.
Despite their public outcry, some experts say India's new nuclear capability may secretly please other Asian states, particularly those in Southeast Asia. They may increasingly look to New Delhi to counter shared fears of Chinese aspirations for political, economic, and military hegemony. "India clearly sees itself as having established South Asian supremacy. Now it seeks to play a wider role, and the Southeast Asian countries seem to welcome that role as a hedge against China," says David Shambaugh, director of the Sigur Center for Asian Studies at George Washington University, in Washington, D.C.
Indeed, experts note that over the past several years, the Association of Southeast Asian Nations - Malaysia, Thailand, Indonesia, the Philippines, Brunei, Singapore, Vietnam, Laos, Burma, and Cambodia - has actively sought to boost military and economic links with India.
Several of these states are embroiled in disputes with China in the South China Sea and all are alarmed over expanding Chinese economic, political, and military ties with the military junta that rules Burma (also called Myanmar).
New Delhi also harbors grave concerns over recent Chinese military activities on Burma's coast on the Andaman Sea, where India maintains major naval facilities on the Andaman and Nicobar Islands.
In addition to refurbishing four naval bases on the Burmese coast, China has built a radar installation on an island that experts believe is designed to monitor Indian military activities and missile tests.
New Delhi also contends that China has moved new nuclear-armed intermediate-range missiles into Tibet, which shares a border with India. Indian officials have cited this among the reasons for this week's tests, its first since 1974.
Beyond a potential rivalry for economic and political influence in Southeast Asia, India and China may be heading for a competition in the Indian Ocean, experts say.
Both countries' economic security is increasingly dependent on oil imports from the Gulf. China's petroleum comes by ship through the Indian Ocean, and Beijing is now expanding its navy in part to protect those supplies.
A larger Chinese military presence in the Indian Ocean - over which India has long aspired to have dominance - could compel New Delhi to accelerate its own naval expansion program, experts say.
The potential for a Sino-Indian rivalry in Asia holds serious implications for the US, which is still the most powerful military, economic, and political presence in the Asia-Pacific region.
In order to safeguard stability in the region, where it maintains 100,000 troops, the US will have to better balance its relationship with both countries while maintaining its commitment to ensuring the security of Asia, they say. That could mean paying more attention to India, which Washington has long ignored in favor of better ties with China.