Now, it's win, win. The children get what they want: soft toys and unlimited time in the shower (whatever happened to boys who wouldn't wash their necks?). The parents get what they want: career satisfaction and unlimited time in the shower.
At first, I was inclined to applaud Mr Clarke. Isn't round-the-clock, state-provided childcare what they get in Denmark and Sweden? Isn't that the secret of achieving gender equality? But then I read Heather McGregor, the Times's pro-boarding mother, and about her extraordinary sons - one of whom learned to "move on" from cuts and bruises at the age of seven - and the doubts set in.
Ms McGregor may be (probably is) a loving, caring mother. But the gist of her case was that boarding schools were more convenient for her or that they did things for her children with which she couldn't be bothered. They made her boys do homework and kept them off computer games and television; her children didn't come home every night, as they would have done from day school, demanding new trainers; they did not go to other people's houses and lust after a PlayStation 2; they could learn a musical instrument without their mother getting the car out. Oh, and since Ms McGregor had to work to pay private school fees anyway (obviously one must), she might as well go the whole hog and pay for boarding.
Well, bully for Ms McGregor. And it seems right that a Labour government should make available to the masses what is available to well-heeled people - even at a cost (according to estimates in The TES last week) of pound;85bn over 10 years.
But just because workaholic adults now choose to spend almost their entire waking hours in one building, we should not assume it is best for children.
The worst thing about boarding schools was not the cold showers, bad food and cane-wielding teachers, but the other children. Almost all children suffer a period when they are the butt of ridicule or the object of physical violence or they just feel left out. The merit of day school is that you go somewhere else in the afternoons and start afresh, with siblings, parents, neighbours, nannies, child-minders, or whatever.
Don't children need to lounge around and chill out? Middle-class parents such as Ms McGregor think children should always be playing the violin, reading improving books or playing chess. They want their offspring to lead the same kind of intense, purposeful, rather joyless lives that they lead.
I think children should have time to wander the streets. I realise many parents are too fearful of traffic and paedophiles to let them out, but at least there is a chance that, in late afternoons, children will temporarily escape adult supervision. But if Mr Clarke has his way, every waking hour will be subject to Ofsted inspection.
I would prefer to change the working world so that either parent can more easily take career breaks, work flexible hours or operate from home. So, I believe, would most parents. If they don't want to spend time with their children, why do they have them in the first place?
Peter Wilby is editor of the New Statesman