I would say: the others do not only fail to materialize, they often point back at economists. If a politician wants to raise taxes, wellfare, or nurses' salaries, the opposing arguments are more often than not economic in nature, and rely on the invisible hand.
It does not follow that economists should take the place of politicians, though. Instead, they should be much more honest, open and direct about their claims, and also point out alternatives. They should, so to speak, grow a conscience.