Early in March, North Korea announced that it had finished work on miniaturizing a nuclear warhead that, if accurate, would enable nuclear blackmail of the U.S., South Korea and Japan. The veracity of Pyongyang's claim is questionable, but the larger threat posed by the North to Japan—and the region more broadly—should not be questioned. North Korea's string of recent provocations—highlighted by its fourth nuclear test and a subsequent missile test—reinforces the need to enhance Japan's security and intelligence capabilities.

Aside from the sustained threat from North Korea, there are other evolving security challenges facing Japan. The most pressing of these is rapid military modernization in China, coupled with Beijing's assertiveness in the maritime domain. This is most acutely threatening to Japan's interests in the East China Sea, where Chinese vessels are constantly entering Japan's territorial waters around the disputed Senkaku islands, which China calls the Diaoyu islands. Of secondary, but not insignificant, importance are Chinese efforts to change the status quo in the South China Sea through land reclamation and gradual militarization of its alleged sovereign territory.

In addition to regional concerns, there are transnational threats that should capture Tokyo's attention. In four years, Japan will be in the final stages of its multi-faceted preparations to host the Tokyo Olympic Games in 2020. In addition to the pomp and ceremony and the diplomatic prestige that the Games bring, there will also be significant pressure on Japan's police, immigration, security and emergency management bodies to fend off potential threats and acts of terrorism and ensure the protection of its critical infrastructure and "soft targets" such as public places and malls.

These concerns also transcend targets within Japan, as Japanese companies and expatriates continue to operate and live overseas—sometimes in unstable environments with rapidly evolving security situations. A key area of concern here remains the Middle East and North Africa, where Japanese companies remain engaged and continue to seek greater market share—especially in the natural resource sector. The hostage-taking—and eventual deaths—in January 2013 of several Japanese nationals working for a gas plant in Algeria is a prime example of these threats.

Since his election in late 2012, Japan's Prime Minister Shinzo Abe has expended a large amount of political time and capital on security and defense reforms. Some of the key changes during Abe's tenure include last year's passage of legislation on the reinterpretation of Japan's right to collective self-defense and reforms to the ability of its Self Defense Forces to assist Japanese nationals in danger overseas. Other key changes include the establishment of Japan's first ever national security strategy, the creation of a National Security Council, new legislation on the security of classified information, revised national defense program guidelines and changes to development and arms exports policies.

Underpinning all these changes is a strengthening of Japan's alliance with the United States through revised bilateral defense guidelines agreed last year. The new guidelines not only serve to strengthen the mutual commitment to the defense of Japan—including the Senkaku islands—but also give teeth to a "seamless" and coordinated approach to evolving security challenges in Tokyo's neighborhood.

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