The destroyer Lassen's vaunted October patrol of within the 12-nautical-mile limit of China's man-made South China Sea islands in October was the first challenge of China's sovereignty over the Spratly Islands since the land-reclamation building began. Officials say the U.S. intends to continue periodic patrols to establish freedom of navigation, laying the stakes for more confrontations.

Six nations in the region lay claim to parts or all of the Spratly Islands, a collection of reefs, rocks and other natural features. In the last two years, China has begun constructing islands on top of the reefs and claiming territorial seas around them to gain fishing and resource rights to most of the South China Sea.

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Heading in to 2016, U.S. officials say that more patrols by Navy ships and aircraft are coming. Legal experts say continuing these patrols are the only way to protect freedom of navigation rights disputed by China. set a precedent for freedom of navigation and that avoiding them to appease China legitimizes the disputed claims.

"We need to remind ourselves that [the] U.S. Navy ... has been conducting freedom of navigation operations since Jimmy Carter was in office," said Craig Allen, a professor of marine and environmental affairs at the University of Washington School of Law. "If you simply acquiesce to somebody else's claims, you could lose your rights."

The Navy's 7th Fleet, based in Japan, does regularly patrols of the South China Sea and other nation's, including Japan, are considering joining the patrols. The Singapore-based littoral combat ship Fort Worth could also be tasked with a patrol but Navy officials say that is less likely — the Navy tends to dispatchsend front-line combatants such as destroyers and cruisers into contested waterstense operations.

The political wrangling over the Spratly Islands will only intensify in 2016 because the international Permanent Court of Arbitration in The Hague, Netherlands, has agreed to hear the Philippines' claims.

Expect the United States to allow the international process to work  itself out while continuing occasional patrols