China's plan to build a second aircraft carrier and the Indian navy's recent test-firing of a submarine-launched cruise missile should be ringing alarm bells in the Persian Gulf.

Beijing and New Delhi are squaring off militarily in the Indian Ocean, the key energy artery from the Middle East and Africa to the Asian giants who need the oil and gas to fuel their expanding economies.

At the same time, both states -- but China in particular -- have sharply boosted investment in Middle Eastern and African energy resources.

These days, more Persian Gulf oil exports goes east than west to Europe and the United States. China, for instance, imports 55 percent of its oil from the gulf.

The U.S. Navy provides the security along the Indian Ocean shipping routes but as the decades-old American domination in the Middle East erodes, and the prospect of a U.S.-Chinese stand-off in the Pacific grows, the strategic dynamics in the Indian Ocean are also changing as China and India seek to secure their access to energy supplies.

It will take a decade or two before the Chinese and Indian navies will be muscular enough to replace U.S. power. It will take years to build enough carrier task forces with powerful air arms and formulate operational war-fighting doctrines, and establish logistics and intelligence networks in the vast region.

That stretches from one strategic choke point, the Strait of Hormuz, the only way in or out of the Persian Gulf, to the Malacca Strait, another vital waterway between Indonesia and Malaysia that links the Indian Ocean with the South China Sea.

Both of these narrow waterways are key channels in the oil and natural gas routes from the Middle East to Asia.

In August 2012, India inaugurated a new naval and air base in the southern tip of the Andaman and Nicobar Islands, a chain of 572 islands strung across the eastern exit of the Bay of Bengal, that will command the Malacca Strait.

Eighty percent of China's oil imports from the Middle East and Africa pass through that 560-mile waterway. All told, 50,000 commercial vessels, 40 percent of the world's trade, transit the strait every year.

The Andaman facility is only one of the new chain of bases and intelligence-gathering centers across the region that India's setting up as it builds its naval, missile and air forces.

China's doing the same thing, with a "string of pearls" network of ports and bases around India's southern periphery.

This runs from the newly opened strategic Chinese-built deep-water port of Gwadar in southern Pakistan, close to the Iranian border and widely expected to eventually contain a naval base athwart the oil routes, along the coasts of Myanmar, Sri Lanka and Bangladesh and to the islands and reefs dotting the eastern edge of the Indian Ocean.

Middle Eastern concerns about a Chinese-Indian confrontation in the region were heightened recently after Rear Adm. Yin Zhou, a senior Chinese navy officer, proposed building a naval base in the Gulf of Aden, taking Chinese expansion even further west than it is now.

Ostensibly, Yin's idea was to support China's naval flotilla attached to the international anti-piracy task force off Somalia.

But given China's naval expansion, it would make sense for Beijing to seek a military foothold in the Gulf of Aden, adding another strategic dimension and threat of conflict to a region already riddled with risk.

The vulnerability of the Indian Ocean route is one reason China's pressing its claim to the Paracel and Spratly islands in the South China Sea so forcefully, increasingly using warships to back its claim.

Vietnam, the Philippines, Malaysia, Brunei and Taiwan also claim the islands, and interestingly, India's state-owned ONGC Videsh energy company has a joint oil and gas exploration venture with Vietnam, pushing its rivalry with China.

The South China Seas islands contain unproven reserves of up to 213 billion barrels of oil, enough to rival Saudi Arabia's proven reserves of 265.4 billion barrels.

If conflict flares there, it could lead to a critical confrontation in the Indian Ocean as well to secure the all-important tankers routes from the Persian Gulf.

With East Africa emerging as the next energy hot zone, the Indian Ocean will become even more important to China and India.