"The basic, simple, biological reality is that women need to be having children when they're 18 - 25 and not when they're 30-45, and they need to be able to do that without having to marry men who are ten years older than they are. "
Why the objection to a 10 year age difference? In my experience, a woman in her twenties is a good match both physically and emotionally with a man in his thirties, ditto woman thirties, man forties, and on into later middle age. Girls mature emotionally much earlier than boys, and young men need the additional time to catch up, while the greater physical strength of men means that a younger woman will still be challenged keeping up with her somewhat older husband (in fact, even at a 10 year age difference, he's going to have to slow down for her, but the older man is much more likely than the younger to have the maturity to do that.) The older husband is also likely to be much more confident in himself as a man, and therefore less likely to seek to dominate her. And sexually, many women go through menopause in their forties, while men in their forties are still going strong.
All around, I think that an age difference anywhere from 5 to 15 years is just about perfect.
If you look back in history, women traditionally were considered ready for marriage around age 18, but they weren't marrying men their own age-- young men weren't considered ready until around 25. Judging from my observations of both my own and my older teenage daughters' generations, I think that's about right.
A 5 year age difference is one thing but if you think more than that is ok - think again. Most women don't want to be at home with a sickly elderly husband while they are still young and strong. Nor do many want to spend a good length of their golden years alone because their much older husband passed on.
I take a lot of heat from the women in my life (and a few of the men) by only dating younger women, usually between the ages of 23-28. The woman I am dating now is in her early 30s but we met when she was 29, so I grandfathered her in.
I'm 37 - I don't find women my age very attractive at all. The ones that are still available tend to be still available for a very legitimate reason: they don't radiate the kind of energy that appeals to me.
walden: Why the objection to a 10 year age difference?
Because if you demand that men wait til they're in their 30's to be married, 99% of them will become serial fornicators, which renders them much less likely to ever marry or to have a stable marriage if they do. The few over-30 men who do stay virgins til the wedding, are really messed up by it (speaking from experience.)
Women can wait, if they have to. But men NEEEEED sex and expecting them to wait til they're "old" (and to a hotblooded 18 year old, 30 is "old), is utterly unrealistic.
In short, 10 years is more often than not a considerable gap in where two people are in life. I wouldn't recomend it.