Moralism warps intelligent endeavour. This is true whether we’re dealing with teenage pregnancies, HIV prevention or human trafficking. Much otherwise good work is stymied and made controversial because there is a hidden agenda beneath it, usually driven by unspoken moralistic aims.
In combatting teenage pregnancies, they would insist we speak only of abstinence and never mention contraception. Why? Because the unspoken agenda is not teenage pregnancies, but the eradication of sex outside marriage. DittoDitto when some people argue that in combatting HIV, we shouldn’t speak non-judgementally about homosex, we shouldn’t remove the stigma or laws against homosexuality (an essential step for public health officials to successfully engage the gay community) because their agenda is not HIV prevention but a campaign against non-heterosexual orientation.