The face of the campaign against repealing the Eighth Amendment will not be a Catholic bishop. It will be a delightful smiling kid with Down syndrome. You can see her in the glossy pamphlets already delivered to homes by the apparently well-funded Love Both group. Her lovely face smiles out at us under the banner headline: “90 per cent of babies diagnosed with Down syndrome in Britain are aborted.” It is a viscerally powerful message: repealing the Eighth is the gateway to a eugenic project in which people with Down syndrome (DS) are engineered out of existence. It’s also an argument that deserves to be treated with respect. To dismiss it merely because it is uncomfortable is both wrong in itself and, for the repeal movement, potentially dangerous.

Any campaign has to be able to take on its opponents, not on their weak points, but on their strongest grounds. Those grounds have changed radically. When the Eighth Amendment was introduced in 1983, it represented things that no longer apply: the political power of the Catholic church, the attempt to stop the liberalisation of Irish social and sexual mores. So the campaign for repeal must not make the classic mistake of fighting the last war. The threat of the “screening out” of people with DS will be at the centre of the new discourse – and those who want repeal had better be ready to address it.