Mavis G, the prospect of you not wanting to fund/encourage SAHP brings up an important point.
Once there is a system of taxation in place that pays for our childcare through allowances etc, the government gets to tell up what childcare is right.
My children have had private nursery, day nanny, school nursery and then out of school club. I do not agree that it is in the best interest of a baby or any under 2s to be in group childcare, based on my own experience. I do not really want my taxes to pay for this kind of childcare. Younger children should be with a day nanny or childminder and then when older should go to a school nursery with extended hours.
But that is just my opinion, while yours is don't fund SAHP, and others will not want to fund a full time nanny or a grandparent or whatever. There is not going to be a consensus.
It would come down to the government to decide, and I don't want them to, because IMO they have ruined state education, and there is no way I want them having any further say in the raising of children.
Because of that, I have to say, I agree with Xenia's proposal and there should be no tax allowances of any kind. Then we can all make our own decisions about childcare. In any democratic society there is a tension between freedom and equality. This thread has gone down the line of wanting to tell other people how to live their lives (not just you, I did it earlier to LLL). I have to then say we are proposing far too much equality at the expense of individual freedoms. I do not want to live in a version of Cuba.