Okinawa Governor Hirokazu Nakaima’s decision to grant the permit to build a U.S. Marine Corps airbase on an offshore landfill near the village of Henoko village is being hailed as an important breakthrough in U.S.-Japanese relations. This move breaks the impasse between anti-base opponents and Tokyo and Washington over where to relocate Marine Corps Air Station Futenma (MCAS Futenma), which the governments in 1996 agreed to close. Washington believes that this development will bolster its rebalance towards Asia and enable it to create a more distributed and resilient military presence there. Many expect the landfill decision to resolve the controversy surrounding MCAS Futenma once and for all, and enable Tokyo and Washington to shift their focus to strengthening U.S.-Japanese security cooperation as a counter to an increasingly powerful and assertive China.

Yet this is wishful thinking. Futenma is not going to go away anytime soon. It took over 17 years to take the first concrete step towards closing Futenma, and the landfill permit is just the beginning of the process to relocate the MCAS—not the end. Base realignments (whether at home or abroad) are a difficult and lengthy process that provides ample opportunities for decisions to be revisited and even reversed. Because of the time needed to construct the offshore airfield in Henoko, the battle over Futenma will continue for at least another decade, if not longer.

While opposition to the American military presence on Okinawa dates back to the post-World War II U.S. occupation of the island, current tensions began in 1995 when three American servicemen brutally raped a 12 year old Okinawan girl. This heinous crime united previously disparate groups that had been opposed to the U.S. military presence, mobilized the Okinawan population, and gave rise to an outspoken and enduring anti-base movement. In an effort to mitigate Okinawan resistance, Washington and Tokyo formed the Special Action Committee on Okinawa (SACO), and tasked it with developing a plan to reduce the U.S. military footprint on the island. In 1996, the SACO report recommended that the United States return thousands of acres of land to the Okinawan prefectural government by consolidating its military presence and relocating many of its bases to the less crowded northern part of the island. The centerpiece of the SACO initiative involved closing the controversial MCAS Futenma, which is located in the heart of the populous Ginowan city, but doing so was contingent upon finding a suitable airfield on Okinawa to replace Futenma, which had proven to be elusive.

There was little progress until 2004, when a U.S. Marine Corps helicopter based at Futenma crashed into Okinawa International University’s campus—a tragedy that reinvigorated efforts to move the airbase to a safer location. In 2006, as a part of the Defense Policy Review Initiative, Washington and Tokyo reached a new agreement, including the relocation of 8,000 Marines and their approximately 9,000 dependents to Guam, but only after Futenma had been moved to Henoko. Like previous plans, however, the 2006 agreement quickly stalled. The election of Yukio Hatoyama of the Democratic Party of Japan as prime minister in 2009 threatened to upend the agreement, as Hatoyama had promised to relocate Futenma outside of Okinawa during his campaign. In Tokyo, Hatoyama’s inability to deliver on this campaign pledge played a significant role in bringing down his government. But on Okinawa, Hatoyama’s broken promise shifted the political landscape and hardened local opposition to the Henoko plan.

After returning to the premiership in December 2012, Shinzo Abe of the Liberal Democratic Party (LDP) sought to enact sweeping defense reforms by reinterpreting Japan’s pacifist constitution so that Tokyo could adopt a more “proactive” defense policy to check China’s growing military capabilities and regional ambitions. A key part of Abe’s defense strategy involves enhancing ties between the Japanese Self Defense Forces and the U.S. military. To bolster relations with Washington, Abe prioritized getting the Henoko landfill permit approved.

Consequently, the Abe administration put tremendous pressure on Governor Nakaima and other Okinawan LDP members to support the Henoko plan and approve the landfill permit in 2013. As a result, five Okinawan members of the Diet publicly retracted their promise to move Futenma off Okinawa. Tokyo also sweetened the deal by pledging to allocate 300 billion yen annually for the next seven years to bolster the Okinawan economy -- with the amount for fiscal year 2014 even higher, at 340.8 billion yen -- and by promising to enforce stricter environmental controls over U.S. bases.

Ultimately, Tokyo succeeded in compelling Governor Nakaima to sign the landfill permit, but he has made it clear that he did so under duress. After signing the plan, Nakaima expressed doubt that the plan was feasible and reiterated that “moving the base outside Okinawa is a better plan.” Nakaima’s statements will encourage those that want to undermine the decision. Moreover, anti-base activists will have ample time to try to scuttle the relocation. Closing Futenma and relocating Marine Corps activities to Henoko will take at least 10 to 15 years—if everything proceeds without any holdups. For example, it took the Pentagon more than a decade to construct a similar offshore airfield at Iwakuni airbase after beginning the process in 1997. That project was also far less controversial in Japan.

In all likelihood, opponents of the plan will not only organize protests, but will also mount legal challenges to the landfill construction on the grounds that it will harm the ecosystem and endanger protected marine animals. Nevertheless, not all Okinawans are implacably opposed to the Henoko airbase. In fact, some believe that there is a pro-base constituency that supports the move because of the financial benefits that it will create. This struggle between the largely silent pro-base faction and the very vocal anti-base movement on Okinawa will ensure that Futenma remains a source of tension in the U.S.-Japanese alliance. In fact, the next phase in the battle over Futenma is likely to begin in the coming weeks when Nago City, which includes Henoko, holds its mayoral election. If incumbent mayor (and base opponent) Susumu Inamine wins the election, which currently appears likely, it will provide fuel for the anti-base movement and increase the pressure to reconsider the choice of Henoko. For the foreseeable future, Futenma is likely to remain the base that has been “closing since 1996.”

Consequently, as long as the Pentagon remains committed to Henoko as the Futenma replacement facility, U.S. policymakers need to avoid complacency and realize that it will take significantly more time and effort before the Henoko airfield is a done deal. Alternatively, if progress on the Futenma relocation once again reaches an impasse, Washington and Tokyo might need to return to the drawing board and consider other options.

Stacie L. Pettyjohn is a political scientist at the non-profit, non-partisan RAND Corporation.

Image: Flickr/Expert Infantry.