I don't know why Don Brash's enemies went to so much trouble exposing his alleged extra-marital excursions. If they were so keen to expose his shortcomings as a potential Prime Minister they should just have encouraged him to talk, especially about Maori, as he did this past week.

Even if it was a cunning political ploy to distract us from his private life, Brash's utterances have reminded us why he shouldn't be Prime Minister.

He lacks the breadth of experience, understanding and insight to lead a country where half the population will - in the not-too-distant future - be Maori, Pacific or Asian. Not that Don would recognise that, because, after all, who is really Maori these days?

Pleasant and well-intentioned Brash may be, but he is yesterday's man. He's the reason South Auckland voters turned out in force at the last election - a vote for Don would have been a vote for a kind of ethnic extinction - despite the fact that many were uncomfortable with Labour's liberal social agenda, in particular the Civil Union bill.

In that respect, South Auckland had something in common with the Exclusive Brethren. The difference is that Southsiders had only their votes to make their point, whereas the Brethren chose the worldly path of political activism, using their not inconsiderable resources to attempt to usher into the Beehive the supposedly more morally compatible and business-friendly National.

The 2000-strong Brethren are as entitled as anyone else to take part in the political process, even if their wealth bought them more clout than they should have been entitled to. It's how they went about it that's questionable.

They will not vote, but the extent to which prominent Brethren members were prepared to get their hands dirty to influence the outcome of the last election and to keep that involvement secret - publishing anti-Labour and Green pamphlets without declaring themselves, attempting to stitch together post-election deals to put National into government, and hiring private investigators to trail the PM, her husband, and others - makes a mockery of their declared detachment from the evils of modern society. But the only people they've managed to bring into disrepute have been themselves.

Whatever we think of the Exclusive Brethren's political muscle-flexing, the increasing mobilisation of the Christian right, galvanised by passionate opposition to gay marriage and abortion, is becoming a feature of political life, here and overseas.

The Los Angeles Times reports this week that the Christian right is mobilising for the November elections, urging pastors to take "a biblical stand" and do everything they can to give the socially conservative Republicans the upper hand in Congress. At stake are the votes of the 30 million churchgoers who didn't vote in the last election.

No one underestimates the substantial pull of this powerful voting bloc, but harnessing the evangelical vote is more complex than it might seem. In the United States the political activities of religious organisations are restricted by a 1954 law that prevents churches and other non-profit organisations campaigning for or against a candidate - a law pushed through by then Senator Lyndon B. Johnson after a non-profit group campaigned against his re-election.

But such has been the level of engagement by religious groups in the US that the Internal Revenue Service told churches they may be in danger of becoming "arms of political campaigns and parties".

Churches can campaign on policy issues, even if it favours a candidate, and many have taken advantage of that loophole.

The Los Angeles Times says one church published pamphlets laying out a candidate's views on aborting "unborn babies".

Despite more blatant violations - donating to candidates' campaigns or putting political signs on their property, only one church has lost its tax-exempt certificate - for sponsoring newspaper ads opposing Bill Clinton.

If churches are pushing the legal limits to influence voters, it's all in the name of a higher calling.

In his international best-seller How Now Shall We Live? former Nixon-aide turned evangelist Charles Colson urges Christians to more actively defend their worldview to create a better world.

"Christians must understand the clash of worldviews that is changing the face of American society," he writes. "We must know not only what our world view is and why we believe it but also how to defend it."

Colson says abortion and homosexual rights are merely skirmishes and that the real war is "a cosmic struggle", not between the worldviews of the Western world, the Islamic world and the Confucian East, as posited by some scholars, but between "the Christian worldview and the various secular and spiritual worldviews arrayed against it".

So, onward Christian soldiers. But where exactly does God stand on abortion and gay marriage? Not everyone is blessed with certitude and the gay marriage debate continues to ignite and divide, as we saw with the Presbyterians last week.

And what of global warming, poverty and the war in Iraq?

Harvard professor and Pulitzer-winning author Edward O. Wilson has appealed to the religious community to put its weight behind efforts to save the environment.

Wilson says science and religion are the two most potent social forces in the US, but religion provides an "intensity of general moral belief and a willingness to take action".

He may be in luck. The evangelical magazine Christianity Today says many Christians are looking for a "kinder, gentler conservatism".

Some, like Brian D. McLaren, named by Time magazine last year as among the "25 most influential evangelicals" in the US, want more tolerance and an emphasis on social justice, once the focus of Christian activism.

As McLaren told one interviewer: "When we present Jesus as a pro-war, anti-poor, anti-homosexual, anti-environment, pro-nuclear weapons authority figure we are making a travesty of the portrait of Jesus we find in the Gospels."