Prime Minister Hatoyama Resigns

So you want a cult in office?

“How do you know for certain it’s a real cult?”

Uh, you’re going to start there?
First off, the Happiness Realization Party is basically the political arm of the Happy Science religious movement. They don’t even try to hide or deny the connection like the Soka Gakkai and the Komeito. Instead they use the argument of freedom of religion to counteract accusations of violating the principle of religion and state. So I think it’s safe to equate one with the other.

And the definition of “cult” that I think we’re both referring to is:

A religion or religious sect generally considered to be extremist or false, with its followers often living in an unconventional manner under the guidance of an authoritarian, charismatic leader.

… according to the American Heritage Dictionary.

From Wikipedia:

Leader Okawa claims to channeled the spirits of Muhammad, Christ, Buddha, and Confucius and claims to be the incarnation of a supreme spiritual being called ‘El Cantare’ from the 9th dimension of “the spirit world”.

Extremist and/or false beliefs, check.
Authoritarian, charismatic leader, check.

Believers fork over large amounts of cash for items like books Okawa has written and holy paintings (enough to set up dozens of candidates for the 2009 election, though they were hopelessly defeated). There are countless accounts of families and friends being torn apart or dragged into it when one person becomes a believer and starts devoting their time to gathering all money and recruits they can get their hands on.

Followers often living in an unconventional manner, check.

All of these sounds like a typical “New Religion” (read: “cult”) that’s been plaguing Japanese society for decades.
Happy Science may not be downright terroristic like the Aum, widespread as the Soka/SGI, or malicious like the Unification Church (mass weddings?), but basically that’s just being “less bad” than the others. I suspect conventional established religions, for all their shortcomings and contradictions will never go away from this world, as not all people are strong enough to never need some group to whisper sweet fantasies and give them purpose in life when the going gets rough … but I digress.

As you say, optimism may be important, which is why the DPJ got elected in the first place partly because they made all these grand promises that gave the uninformed great hopes of a better life if they just shed the shackles of the corrupt LDP regime … and look where that went. So hopefully that isn’t your only criteria.