merrymouse Are you seriously suggesting their is no psychological element to carrying, birthing and feeding an infant? Do you not consider this builds a very complex bond?
I'm not saying that it has no impact, but I think it's insignificant compared to the bond created by actually caring for a child after birth. I also don't think breastfeeding is necessary to create a bond with a child. I breast fed my children, but I don't think it created a bond that was intrinsically superior in any way.
association between positive thoughts and feelings about the infant during pregnancy and later interaction with the infant, but only in mothers.
Only mothers can become pregnant, so it would be very surprising if fathers shared the same feelings about being pregnant.
However, some mothers have a very negative experience of pregnancy and birth. There is no universal experience of birth. Fathers, and adoptive parents also clearly form strong bonds with their children and some birth mothers do not (just look at the toxic parent threads).
40% of children nowadays have insecure attachments.. I'm really not sure what to do with that information - do you think 40% of children are doomed because of their insecure attachments? If the number is that high, I'd question whether attachment is that important.
I’m afraid the evidence about the advantages of breastfeeding are irrefutable
There is evidence that breast feeding is better, but the degree to which it is better is not clear and different studies provide different results.
but unpopular with those who chose not to or who see infant feeding as in some way oppressive.
Again, I breast fed my children. I just don't think there is evidence to show that it makes a massive long term difference that overrides all other influences. You seem to discount all the very negative experiences of breast feeding that some women have.