Tensions between China and Japan have flared up again after heavily publicized political stunts by nationalists over uninhabited islands in the East China Sea that both countries lay claim to.

The islands, known as Diaoyu in China and Senkaku in Japan, continue to elicit strident nationalism among their respective populations. But these episodes are just the latest in a series of tit for tat actions across Asia that is increasing the chance of events spinning out of control and resulting in a regional conflagration.

The latest tensions began in September 2010 when a Chinese fishing trawler rammed into a Japanese Coast Guard vessel near the disputed islands. The incident, caught on tape which clearly showed Chinese culpability, drew spirited nationalist reactions in both countries. The Chinese captain was arrested but was released in just two weeks when China moved to cut off the export of rare earth minerals to Japan which are used in the production of high technology equipment.

The outcome made it clear that Sino-Japanese relations would be subject to the whims of nationalism to a greater degree than had been the case in the past.

This April, the outspoken governor of Tokyo, Shintaro Ishihara, announced in a speech to the conservative Heritage Foundation in Washington DC that he would purchase three of the Senkaku Islands, under ownership of a Japanese family for decades, “in order to protect them.”

Although a ruling party member, Prime Minister Yoshihiko Noda’s cabinet called “Ishihara’s shtick only good for gaining momentary popularity.” The Chinese government denounced the move and said it would take “necessary measures” to defend its sovereignty. In a bid seemingly to defuse the crisis, Noda indicated that the central government may nationalize the islands instead, however this only further enraged Chinese nationalists.

Earlier this month, fourteen Chinese nationalists, along with two reporters from Phoenix TV, landed on what they call the Diaoyu Islands. After successfully evading the Japanese Coast Guard on an old fishing boat, they were quickly arrested and returned to Hong Kong two days later to a hero’s welcome. Their eviction sparked thousands of Chinese to take part in major anti-Japanese demonstrations in a dozen cities across the mainland.

This week, a group of some one hundred Japanese nationalists, accompanied by several members of parliament and a Reuters reporter, sailed to the islands too. Nine Japanese managed to swim ashore, bypassing the Coast Guard to plant the Japanese flag before being evicted themselves.

One reason both governments failed to prevent tensions from increasing is because leaders need to avoid appearing weak in front of their populations for domestic political reasons.

This unwillingness to control nationalism threatens to let a minor dispute, in this case over rocks, albeit rocks that potentially contain vast deposits of natural gas and imply abundant fishing rights, escalate into a serious crisis with the risk of drawing the United States into a war with China due to its treaty obligations to Japan as well as the Philippines.

All the more worrying is that this latest spat comes amid other island disputes flaring up in the region. Indeed, tensions in the East China Sea are merely part of a game of one upmanship happening across East Asia. The summer of 2012 may well be remembered as the time when long dormant disagreements over territory began to boil over.

In July, Russian prime minister Dmitri Medvedev stirred controversy when he landed on a disputed island of Russia and Japan in the Southern Kuriles, which Japan calls its Northern Territories.

South Korea’s Lee Myung-bak, also in July, made an unprecedented visit for a sitting president to the disputed islands of Dokdo, which are called Takeshima in Japan, causing Tokyo to file a protest and withdraw its ambassador from South Korea.

Over the past few months in the South China Sea, tensions between China and Vietnam have escalated over their mutual claims to the Paracel or Xisha and the Spratly or Nansha Islands as well as between China and the Philippines over the Scarborough Shoal. The ASEAN summit in Cambodia failed to find a resolution to the crisis and turned into a catastrophe when the participants could not even agree on the wording of a joint statement at the end of the meeting.

These territorial feuds are a recipe for disaster given the lack of security arrangements in Asia that exists in Europe with NATO. Some in the region have questioned the continued commitment of the United States in maintaining Asia’s security in the face of looming defense budget cuts and a persistently weak economy.

Against the backdrop of China overtaking Japan as the world’s second largest economy and its military growing exponentially, coupled with increasing Sino-Japanese tension, the American presence in the region remains critical to the future security of Asia.