MOST politicians and their supporters react with joy when they win leadership battles with large majorities. Not in Japan. On Sept 21, when Prime Minister Yoshihiko Noda convincingly defeated party rivals for the post of president of the left-leaning Democratic Party of Japan (DPJ), he looked glum.

“I am not smiling,” he told supporters in a speech soon after being re-elected. It was not difficult to see why. By all accounts, the Prime Minister will spend the next few months trying to maintain a precarious balance between preserving party unity and addressing major policy issues demanding attention.

The latter include accelerating the pace of rebuilding after last year’s earthquake, reviewing the nation’s nuclear energy policy and dealing with diplomatic spats involving China and South Korea.

And, as is becoming increasingly clear, he must do all this as an ambitious former prime minister snaps at his heels. Less than a week after Mr Noda won re-election as DPJ head, the Liberal Democratic Party (LDP) held its party poll, choosing as its leader Mr Shinzo Abe, a former premier known for his hawkish views.

Apart from potentially complicating Japan’s relations with China at a particularly sensitive time in diplomatic relations, Mr Abe is likely to insist that the Prime Minister honour a deal he made in August with Mr Abe’s predecessor. This involved both the LDP and New Komeito – a smaller opposition party – supporting legislation to double the 5 per cent sales tax rate by 2015 in return for an undertaking from Mr Noda to call a general election “some time soon”.

Constitutionally, an election does not have to be held for the Lower House until next August.

But the opposition is probably expecting it no later than next January. This is the date Deputy Prime Minister Katwuya Okada reportedly mentioned when he approached LDP leaders privately about the matter in July. Mr Noda, however, may be wishing for more time. A survey last month by the Nikkei business daily showed that only 14 per cent of respondents supported the ruling DPJ, while 35 per cent chose the LDP. Other voters supported minor parties or professed no preference.

While the reason the LDP wants an early election is obvious enough, Mr Abe might be better off waiting a few more months for the DPJ to destroy itself.

The DPJ came to power in 2009 after more than 50 years of LDP rule pledging to make fundamental changes in the way Japan was governed. Since then, critics charge that the party has failed to live up to its promises, particularly with regard to its pledge to cut the bureaucracy. Instead, the DPJ has become known for infighting.

The sad fact is that although Mr Noda won 68 per cent of the vote in the party ballot, he did so largely because party members didn’t see any credible alternatives. Voter turnout was just 33.7 per cent, the lowest ever.

Several party members in both the Upper House and Lower House are also believed to be considering joining opposition groups in an attempt to save themselves from political oblivion in the next election. If just nine Lower House members leave, Mr Noda will lose his majority.

For the moment, Mr Abe appears to be content to play the role of responsible opposition leader. He has said, for example, that the LDP will not oppose Bills “at any cost”. Most observers have taken that to mean he will support the passage of key finance Bills such as one to allow the government to issue deficit-covering bonds to finance the fiscal 2012 budget.

Mr Abe may also wish to leave Mr Noda the unenviable task of making the unpopular but necessary decisions needed to ensure Japan’s economic future. These include backtracking on an initial decision to eliminate the use of nuclear power by 2030, and joining regional free trade agreements such as the Trans-Pacific Partnership (TPP) led by the United States. Japanese involvement in the TPP is strongly opposed by the influential farm lobby.

“There are times when I have to make decisions even if it means dividing the party or public opinion,” Mr Noda said in his victory speech last month. “I have felt the weight of that intensely over the past year.”

On Oct 1, Mr Noda reshuffled his Cabinet for the third time this year. The move involved promoting junior legislators dissatisfied with his administration to Cabinet positions in an attempt to maintain internal party unity and boost popular support.

The idea that Japan needs strong leadership to overcome its longstanding economic difficulties hardly seems in question. If Mr Noda cannot deliver, can Mr Abe? His track record does not inspire confidence. He resigned as prime minister in 2007 after a series of financial scandals and political gaffes that forced several of his ministers to quit. Voters also saw him as being out of touch with their economic concerns.

Whether the elections come early or not, Japan is likely to continue to suffer from a leadership vacuum for some time to come.

(C) Singapore Press Holdings Limited