Tensions in the South China Sea have been high in recent years, due in large part to territorial disputes between Asian nations over the ocean waterways in the region.  China, Taiwan, Vietnam, Malaysia, Brunei, and the Philippines all have contradictory jurisdictional claims in the area, driven by military posturing and the possibility of massive oil and gas reserves.

The United States, which boasts the most powerful Navy on the planet, has made a concerted effort to curb the possibility of armed conflict in the region, as the American economy is closely intertwined with the major economies in the area.  America’s ongoing agreement with Japan preventing them from establishing a traditional military force since the end of World War II places the U.S. in the precarious position; as allies with South Korea, the Philippines and Japan, the U.S. must navigate these complex waters in a political sphere as well as a naval one, and doing so just got a bit tougher.

A recent report by the global financial services company, IHS Markit, states that China is currently on track to nearly double defense spending by 2020, increasing from $123 billion annually in 2010 to $233 billion in the next three years.  That $233 billion figure would place China’s defense spending at about four times what America’s closest ally, the United Kingdom, spends annually and would exceed the defense budgets of all of Western Europe combined.

This dramatic uptick in defense spending has raised a number of concerns about the possibility of armed conflicts breaking out in the region, as increased spending will undoubtedly result in an increased Chinese military presence throughout the South China Sea.  Having more active military personnel and equipment in the region not only increases chances of intentional posturing erupting into violence, but it also increases the likelihood of unintentional international incidents occurring that could stoke the fire between nations.

Chinese military aircraft intercepted U.S. reconnaissance flights in an “unsafe manner” over international waters in the region twice this year, each time prompting political statements from both nations regarding whether the aggressive Chinese approach was appropriate or not.  In both events, the U.S. planes were on what they called “routine patrols” when Chinese fighters came within unsafe distances of the American planes.

“It must be pointed out that U.S. military planes frequently carry out reconnaissance in Chinese coastal waters, seriously endangering Chinese maritime security,” China’s Foreign Ministry spokesman Hong Lei Hong told reporters after the first of two incidents.  “We demand that the United States immediately cease this type of close reconnaissance activity to avoid having this sort of incident happening again,” he continued.

Although China’s aggressive stance about their own coastal airspace has prompted possibly dangerous aerial interactions, those concerns don’t extend to the coastal airspace of other nations.  Earlier this week, China claimed Japanese aircraft engaged in “dangerous and unprofessional” behavior when they intercepted Chinese military aircraft flying between Japan’s Okinawa and Miyako islands.  It’s worth noting that a large American military installation is located on the island of Okinawa as well.

India has also dramatically increased defense spending recently, prompting some experts to fear the two nations could start a regional arms race.  They spent a reported $50 billion on their military in 2016, edging Russia out of the top five defense spenders for the first time, and are slated to take the number three spot from the United Kingdom by 2018.