President Donald Trump has made no secret of his skepticism toward Americaís most important security pacts and military commitments, sending shockwaves throughout East Asia in April when he suggested that Japan, among others, should pay more for American protection and arm themselves with nuclear weapons to deter North Korea. The Japanese government relies heavily upon its mutual defense treaty with the United States for its national security, as Article IX of the Japanese Constitution strictly limits the nationís war-making capacity. Trumpís electoral victory in November thus has startling implications for the island nation, prompting some question as to whether Japan should start pursuing a more conventional military arrangement for its own self-defense. However, the prospect of a rapidly aging population and a dwindling labor force will serve as an obstacle to future military self-sufficiency.

The Imperative for an Expanded Military

Following Japanís defeat in the Second World War, US-led occupation forces drafted a new constitution in which the nation relinquished its right to wage war. The United States subsequently signed a security treaty with Japan, permitting the United States to maintain permanent military bases on Japanese soil ďto deter armed attackĒ against a pacified, and thus vulnerable, Japan. US authorities also encouraged Japan to maintain a limited self-defense force to guard against growing Communist elements in China and Korea. However, the Self-Defense Forces (SDF), now composed of roughly 247,000 active personnel, engage primarily in international peacekeeping and disaster relief.

This military arrangement has become an increasingly vital element of Japanís security, as tensions escalate with China over the Senkaku or Diaoyu Islands in the East China Sea. Moreover, Japanís position within the American nuclear umbrella is perhaps more important than ever, as Pyongyang pursues an aggressive nuclear weapons development program.

Trumpís isolationism and his ďAmerica firstĒ foreign policy disposition, however, increase pressure on Japan to bolster its own defense capabilities and prepare for increased self-reliance. President Trump intimated during the election campaign that he may withdraw the 50,000 US troops currently stationed in Japan if the country does not contribute more to finance their operations. In light of this and similar alarming remarks, the aforementioned long-standing security pact between the United States and Japan clearly rests on uncertain ground. This might explain why Prime Minister Shinzo Abe was the first foreign dignitary to meet with President Trump and establish rapport in the days following the US election.

It must be noted, however, that the Abe administration was already seeking to expand the role of the nationís military on the global stage well before the conclusion of the US presidential election. Since the beginning of Abeís tenure in 2012, Japan has established a new National Security Council, lifted a nearly fifty-year-old ban on weapons exports, and reinterpreted Article IX of the constitution to permit collective self-defense, meaning that Japan may defend an ally that is under attack, even if there is no threat to the homeland. Abe, additionally, seeks to amend that very article to exclude a provision banning land, sea, and air forcesóa provision that some scholars have argued renders the SDF unconstitutional. Meanwhile, the Defense Ministry has repeatedly requested an increase in its budget in order to purchase antiballistic missiles, surveillance drones, beach-assault vehicles, and aircrafts.

The Japanese public is loath to depart from the countryís pacific traditions. There remains a general fear that the country might return to the style of extreme militarism that characterized its politics in the 1930s. However, whether through the defense initiatives of the incumbent prime minister, the assertiveness of China and North Korea, or the isolationist disposition of the incoming American president, Japan is facing pressures which could make some military expansion all but imperative.

The Pressures of a Vanishing Workforce

Despite the signs that the country may need greater military self-reliance, Japanís steadily aging population presents a substantial impediment to remilitarization now and in the coming decades. Japan suffers from one of the lowest birthrates in the world, while enjoying a remarkably long life expectancy. This trend has resulted in steep population decline. The population peaked at approximately 128 million in 2010, and subsequently shrunk by roughly 1 million by 2015. Japanís population is projected to fall to 86 million by 2060 and to reach extinction in one thousand years. According to the Statistics Bureau, as of 2014, 33 percent of the population is over the age of 60, while only 12.8 percent is age 14 or younger.

These demographic trends will have an adverse impact on the labor market, as the proportion of retirees and pensioners skyrockets and the proportion of working age citizens steadily diminishes. Given the nationís strict immigration policies, there is no significant influx of foreigners to compensate for this labor shortage.

This impact is especially acute for the SDF, whose all-volunteer workforce already struggles with recruiting, as many young people choose higher education or private industry over military service. According to a recent report from the Ministry of Defense, the number of people eligible to join the SDFócitizens age of 18 to 26óhas dramatically decreased from a height of 17 million in 1994 to 11 million in 2015. Another report from the Brookings Institution projects that, at current rates of depopulation, Japanís Air Self-Defense Forces alone will be forced to close three bases by 2025. If these demographic trends continue, developing a stronger and more self-reliant military will be a challenging prospect.

Of course, the SDF could rely more heavily on technology, such as unmanned aerial systems, to bolster their military capability and mitigate the effects of lagging recruitment. However, a robust ground force is surely needed for the SDFís work in peacekeeping missions and domestic emergencies such as the 2011 Tohoku Earthquake.

Trouble Ahead

Japan is thus pulled in two directions. The transition of power in Washington, in concert with the shifting balance of power in East Asia, signals the need for a more self-sufficient fighting force befitting its role as the third largest economy in the world. However, the pressures of a steadily aging population may stymie those efforts, as available manpower dissipates and funds are diverted from the defense budget to healthcare and social security for the elderly. How these developments will shape the US-Japan relations in the next four years remains to be seen. However, they will surely remain a fixture of Japanís foreign and domestic policy challenges in the foreseeable future.