The rift was followed by the rise of the Japan Restoration Association led by Osaka’s mayor, Toru Hashimoto, and the consolidation of the neoliberal Your Party as challengers to Japan’s two major parties, suggesting that Japanese politics may be on the brink of a new party realignment.

Observers should not place too much significance on changes to the parties — over the past 20 years Japanese parties have formed, splintered, dissolved and merged frequently. Japan, however, may be in the midst of a wider-reaching political transformation that extends beyond the party system.

In 2012 Tokyo has seen the biggest demonstrations in Japan in more than 50 years, as tens of thousands of protesters have repeatedly converged on the prime minister’s residence to protest against Prime Minister Yoshihiko Noda’s decision to restart the nuclear reactors that were shut down after the 3/11 disaster. The anti-nuclear protests come on the heels of smaller-scale protests in late 2011 and early 2012 against the Noda cabinet’s intention to join the Trans-Pacific Partnership talks. These protests, together with reports of growing participation in political ‘training’ academies sponsored by reformist politicians, including Hashimoto, suggest that a public long dissatisfied with its political leaders is increasingly inclined to take politics into its own hands. Whether out of disappointment of the DPJ’s performance or dismay at the persistence of structural corruption in the Japanese state, public distrust may have reached a tipping point.

Although the Tokyo protests inspired comparisons to the Arab Spring and Hashimoto’s rise to the Meiji Restoration, it is too early to tell where the tumult will lead. Typical of a mature democracy, Japan’s political, electoral and administrative institutions serve as considerable barriers to political outsiders seeking entry.

First, the mixed-member electoral system for the House of Representatives is advantageous to major parties that are able to run candidates in nearly all of the 300 single-member districts. It is unclear how many candidates the expected alliance between Your Party and Osaka Restoration Association will be able to field in the next general election, which must be held by August 2013. And campaign finance and electoral activities laws favour incumbents, most of whom belong to the two major parties.

Moreover, the House of Councillors is a significant roadblock in the path of would-be reformists. If the opposition controls the House of Councillors, it will be able to stall or block the government’s agenda, as has happened during the past five years, when the opposition controlled the House of Councillors for all but one year. While half of the House of Councillors faces re-election in 2013, the fractured party system may make it difficult for any party to win an outright majority, forcing the ruling party to reach ad hoc compromises with the opposition. If a populist party or coalition could form a government on the basis of a lower-house majority, a divided Diet (nejire kokkai) might nevertheless hamper its ability to govern.

Finally, a populist government would have to contend with Japan’s national bureaucracy. The bureaucracy’s influence — and its hostility to reformist politicians — can be overestimated, but politicians must still manage even the most pliant bureaucracy. Neophyte ministers, even those with policy expertise, may not necessarily make skilled managers of the bureaucracy. This appeared to be the case with the DPJ after 2009. Without outside advice of the kind that legislative staff and think tanks might provide, political leaders have little choice but to reach some kind of understanding with the bureaucracy. Democratic legitimacy may ultimately depend on a neutral, competent national bureaucracy that is capable of administering the programs that voters want. In their zeal to reform the bureaucracy, politicians have ‘hollowed out’ the civil service by driving out or discouraging talented individuals and impairing the bureaucracy’s ability to provide sound policy advice.

Despite mounting unrest in the Japanese political system, significant obstacles stand in the way of lasting change. Few of Japan’s policy challenges have easy solutions. And despite the desire for a decisive leader, Japan, now more than ever, may need institutions in which more views are represented and compromise is easier. Prime Minister Noda has shown that reaching a compromise, while difficult, may not be impossible. But while the demonstrators in Tokyo and the urban reformists of Osaka are unlikely to see the broad changes they desire, they may yet leave their mark on Japanese politics. If frustration with the system produces an influx of new participants, Japanese democracy may become more open, and more willing to absorb new ideas from outside the centres of power within the Diet.

Tobias Harris is a doctoral candidate at the Massachusetts Institute of Technology. He worked for a DPJ member of the upper house of the Diet between 2006 and 2007.