A week is a long time in politics, as the old cliché has it, but for Japan's Sunrise party four days was a whole lifetime.
In an illustration of the febrile state of politics in Japan, the party appeared and disappeared in a span of days – an even shorter lifespan than such classic Japanese emblems of impermanence as the cherry blossom and summer cicada.
Last Tuesday, rightwing former Tokyo governor Shintaro Ishihara announced the formation of the Sunrise party as one of a host of new groups hoping to become a new "third force" challenging Japan's two big ruling and opposition parties.
On Thursday, the Sunrise party said it would merge with Tax Cut Japan, another would-be third force contender. But on Friday, the party scrapped that plan, and the following day folded itself into the recently created Japan Restoration party.
Such a sharp narrative arc is unusual even in Japan where party turnover is notoriously rapid. Yet the setting of the Sunrise party is hardly the end of the story. Its unification with the Japan Restoration party has brought together two of Japan's most high-profile nationalist figures: Mr. Ishihara and Toru Hashimoto, the charismatic mayor of the western city of Osaka.
Mr. Ishihara and Mr. Hashimoto hope to capitalize on widespread disillusionment with the ruling Democratic party and with the Liberal Democratic party, which dominated politics until ousted by the DPJ in 2009.
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The Nikkei newspaper published a poll on Monday which gave the Restoration and Sunrise parties a combined 15 percent share – just one percentage point less than the embattled ruling DPJ. About a quarter of respondents said they planned to vote for the LDP.
Other polls suggest weaker backing for the newly merged nationalist insurgents, but their rapid rise is worrying many mainstream politicians.
Mr. Ishihara is a harsh critic of China who sparked a crisis in Sino-Japanese relations earlier this year by trying to buy a group of islands at the heart of a territorial dispute with Beijing.
Asked by the BBC how Japan should respond to recent Chinese challenges to its control of the island, Mr. Ishihara said simply: "Be ready to draw the sword".
Prime Minister Yoshihiko Noda has warned that "tough talk" is becoming an unwelcome feature of discussion of Japan's security policy.
"This kind of [extreme nationalist] atmosphere or mood is emerging . . . and it's possible that tough talk could captivate the public, but that would be the most dangerous thing for the nation," Mr. Noda told the Financial Times in an interview on Sunday.
The Restoration party faces fierce competition from other wannabe third forces. Announcements of new parties or mergers between existing groups have proliferated as politicians gear up for the general election on December 16.
Other contenders include a group set up by one-time DPJ heavyweight and election-wizard, Ichiro Ozawa. And on Monday, a former DPJ farm minister teamed up with the ruling party's ex-coalition ally Shizuka Kamei to form a new party that will campaign against trade liberalization.
Many new groups are handicapped by a lack of ideological coherence. Most mergers appear to owe little to shared policy goals – as suggested by the Sunrise party's original desire to wed both Tax Cut Japan and the Restoration party, which supports higher consumption taxes.
Mr. Ishihara and Mr. Hashimoto also appear to differ on key policy issues such as territorial issues, nuclear policy and tax.
Koichi Nakano, a political scientist at Sophia University, says their new Restoration party is likely to struggle to stay united, especially given the famously assertive and individualistic leadership styles of its two leaders.
"More than policy differences, the real problem is likely to be the clash of egos."