Who runs the world's second-richest country? Certainly not the hapless Yoshiro Mori, Japan's error-prone Prime Minister.

While Mr Mori has proved more pliable than some of his predecessors, prime ministers have traditionally served as little more than fronts for the backroom operators in the Liberal Democratic Party.

But this week, the LDP, the pivotal political force for most of Japan's postwar history, has been kowtowing to a more potent strength - one of its own junior coalition partners.

New Komeito, a group of largely nondescript MPs, has emerged as the most important element of the Mori Government as a result of the shakeout from last Sunday's national election.

"Who is the real power in the Government now? Undoubtedly it is Komeito," a veteran political analyst, Shigenori Okazaki, said.

"The LDP is probably at its weakest position ever. Its electoral survival now depends firmly on its coalition partner."

With the third coalition partner, the New Conservatives, reduced to a rump, the LDP needs New Komeito's support to get legislation through both houses of parliament.

It is a state of reliance unprecedented for the once almighty LDP. For many Japanese, it is a development as alarming as it is unexpected. While its consensus-driven, dynastic nature has made Japanese politics a predictable, almost irrelevant, animal for much of the population, New Komeito arouses deep and conflicting emotions in the electorate.

To its fanatical supporters, it is the only entity in Nagatacho, Tokyo's political headquarters, capable of delivering policies that directly improve the lot of ordinary people.

To its critics, and they are legion, it is a stain on the political system, flouting the strict constitutional separation of state and religion.

The deep conflict arises from New Komeito's relationship with Soka Gakkai, a giant lay Buddhist organisation dominated by its spiritual leader, Daisaku Ikeda.

Soka Gakkai (the name means Value-Creation Society) was set up by two teachers in the 1920s to further the beliefs of an influential Buddhist sect, Nichiren Shoshu. One of its founders, Tsunesaburo Makiguchi, died in prison during World War II for refusing to bow to state-enforced Shintoism.

But it is a postwar boom that has given Soka Gakkai its clout (and its notoriety). Using the massive funds generated by its 8 million members, mostly housewives and small business people, Ikeda has been able to build Soka Gakkai into a giant global organisation, aimed at "promoting peace through culture and education".

The expansion has not done much for its domestic image. Despite its lofty goals, some heavy-handed recruiting tactics in the 1970s and 1980s and its intolerance of criticism have left many Japanese deeply suspicious of the body and its leadership.

"To me, New Komeito is little more than a cult, like Aum [Shrinrikyo, the doomsday organisation behind the 1995 Tokyo subway gassings]," one conservative voter in central Japan complained during the election campaign.

While it strenuously denies being manipulated by Soka Gakkai, New Komeito openly acknowledges that the religious body provides it with the bulk of its electoral support.

To the LDP, struggling to find an urban support base to prop up its aging rural one, New Komeito's vote-marshalling skills are priceless. While Komeito was hammered on Sunday, with its Lower House representation falling from 42 to 31, it was still able to deliver more than 7.5 million votes to the conservative cause, mainly in the dense urban corridor between Osaka and Tokyo where the LDP was routed.

Mr Okazaki calculates that without Komeito, the LDP would have been left with only 184 seats in the 480-seat Diet, instead of 233. (Before the election it boasted 271 out of 500 seats.)

But New Komeito's support is a double-edged sword for the LDP. Many of its own supporters dislike the tie-up intensely. LDP voters point-blank refused the entreaties of their leaders to extend electoral co-operation to Komeito candidates.

Some Komeito officials are warning privately that they may abandon the electoral tie-up at next year's Upper House elections, simply to protect their own Upper House members.

But most experts believe the fate of the LDP and New Komeito are so deeply entwined that the LDP chieftains will do everything possible to shore up the vote of their partners next year - and that means deep spending on the populist welfare initiatives that Komeito espouses.

"You can say that Komeito now operates like a faction inside the LDP," another commentator, Minoru Morita, said.

That factional clout even complicates the LDP's task of choosing its own leader. While many inside the LDP would dearly love to get rid of Mr Mori, one of the party's most eligible replacements, a former LDP chief secretary, Koichi Kato, is a trenchant critic of New Komeito.

"The reality is that New Komeito will decide Mori's fate. It will also decide who replaces him, and when," Mr Okazaki said.

"There is no stability at all in this administration. It is a much weaker Government."

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