Writing sometime around the 10th century BC, the furious author of Psalm 14 thundered against those who say there is no God. "They are corrupt, they have done abominable works, there is none that doeth good." If the denunciations of wicked atheists coming from today's apologists for religion are any guide, the spirit of Iron Age Israel is abroad in 21st-century Britain.

In advance of the pope's visit, clergymen and commentators are deploying every variety of bogus argument against those who advocate the superiority of secularism. Edmund Adamus, director of pastoral affairs for the Catholic diocese of Westminster, led the way when he denounced the "wasteland" secularism produced. If he had been condemning the atheist tyrannies of communism and fascism, I would have no complaint. However, Adamus was not objecting to Cuba, China or North Korea, but to the wasteland of secular, democratic Britain "with its ever-increasing commercialisation of sex, not to mention its permissive laws advancing the 'gay' agenda".

Rightwing columnists and, depressingly but predictably in these appeasing times, leftwing journalists have joined the moaning chorus. The arguments of Geoffrey Robertson QC and Professor Richard Dawkins that the cops had grounds to ask the pope to account for his church's failure to stop the rape of children in its care drove them wild. "The hysterical and abusive nature of some of the attacks on the pope will do nothing but discredit secularism," said Andrew Brown in the Guardian. "I accept, of course, that lots of secular humanists are tolerant and reasonable people," says the more restrained and judicious Stephen Glover of the Mail. "But there is a hard core which embraces and promotes atheism with the blind fervour of religious zealots."

Not all of those who condemn atheism are pious themselves, as the presence of journalists among their number suggests. Rather, they believe in piety for the masses and fear that without religion the lower orders will lose their moral bearings. "All religions are equally sublime to the ignorant, useful to the politician and ridiculous to the philosopher," said Lucretius. And behind many of the demands of today's religious apologists that we "respect" Catholicism, Islam, Hinduism, Judaism and even the Scientology cult lies a desire to keep the plebs in their place by protecting their ridiculous but politically useful beliefs. Although I am proud to be on the board of the National Secular Society, Britain's most urgently needed pressure group, I am not a militant atheist. I have seen too many vicars being moved by their Anglicanism to dedicate their lives to others to agree with Christopher Hitchens's bald statement that "religion poisons everything".

But the notion that in free countries atheism promotes intolerance and immorality is demonstrably false. Last year, Californian sociologist Phil Zuckerman responded with facts rather than witless abuse to claims from Christian psychologists and theologians that atheists were "selfish and pusillanimous curmudgeons", "unnatural" or "just damn angry". He pulled together the available evidence and found that the more atheists or agnostics a free society has the more moral it becomes.

Predictably, atheists were far more likely to be tolerant supporters of women's rights and gay rights than believers. The pope, like militant Islamists, orthodox Jews and the ultras in every faith cannot see that struggles for female and homosexual emancipation are among the most moral causes of our age. But as believers in a sternly misogynist and homophobic god, they must want to be tough on crime.

If so, they should welcome the contribution that atheists make to promoting law and order. A study in the 1990s found that a meagre 0.2% of the US prison population were atheists. In America, the states with the highest murder rates tend to be highly religious, such as Louisiana and Alabama, but the states with the lowest murder rates are among the least religious in the country, such as Vermont and Oregon.

True, there is some evidence to suggest that atheists and agnostics are more likely to engage in underage drinking and illicit drug use. But the wider conclusion on the links between crime and religious belief holds good: if you want safe streets, move to a godless neighbourhood.

Atheism and secularism, Zuckerman continued, are also correlated with higher levels of education and lower levels of prejudice not only against women and gays, but people from other ethnicities as well. For good measure, atheists were less likely to beat their children and more likely to encourage them to think independently.

In many US courtrooms, judges restrict or deny child custody rights to atheist parents. If they want children to grow up to be law-abiding citizens, and not end up back in court as juvenile delinquents, they should stand that policy on its head.

What applies at city and state level applies internationally. Sweden, the most secular country in the world, gives the highest proportion of its gross domestic product in aid. Of the top 10 aid donors, only the United States is a strongly religious country. Needless to add, the oil-rich and religion-saturated Iran and Saudi Arabia are nowhere near making the premier league of charitable nations, which should not be a surprise because Iran concentrates its overseas efforts on exporting terrorism, while Saudi Arabia uses its petrodollars to promote its brutal Wahhabi theology.

An easy point to make is that secular democrats do not stone women to death for adultery or murder Afghan teachers for the crime of teaching girls to read and write. But it is not entirely irrelevant to the argument about the papal visit. Robertson's and Dawkins's enemies can accuse them of being "hysterical" and "abusive" and in the grip of the "blind fervour of religious zealots" while knowing that secularists will not respond by trying to kill them. Ever since the ayatollah Khomeini's fatwa against Salman Rushdie they have not dared use the same language about real abusive and hysterical zealots, who just might.

Not that I agree with Robertson and Dawkins that the police should arrest the pope. The best way for anyone caught up in religious crimes to make amends is to convert to secularism. The odds are that they will be better people for it.