Many marriages, especially in the upper-middle class, were strengthened by caution and delay. But for couples with more limited resources, and more to lose from failure, no-fault divorce may have reduced the value of the institution and the sacrifices embraced on its behalf.
When liberals claim social conservatives don’t have any policy ideas for marriage promotion, then, they’re somewhat self-deceived. A sustained conservative shift on abortion policy and marriage law probably would, over the long term, increase the rate at which couples take vows and stay together, and improve the life prospects of their children.
So one hypothetical middle ground on marriage promotion might involve wage subsidies and modest limits on unilateral divorce, or a jobs program and a second-trimester abortion ban.
The chances of liberals embracing this hypothetical are … nonexistent. Which is fair enough — the belief that some personal liberties are nonnegotiable whatever their policy implications is obviously sincerely held, and I can respect a worldview that privileges moral absolutes over social science evidence.