I've been feeling a little cross at the way parents are being treated by schools. I have to confess an interest here. In short, I am a parent.I am therefore on the receiving end of a number of rather patronising and threatening letters from my children's school, warning me how much I might be fined for taking them out without permission.
Of course, I'm not in favour of parents just taking children out of school on a whim. I know, I know, school is important. My children need their education and - even more important - the school needs to meet their attendance targets. I know what's what.
What I find unacceptable is that, by tying parents to the school term dates in such a draconian way, they fling us into the embrace of the travel companies - who have no compunction about the massive hike in their prices during the school holidays.
This is fine if you can afford it, but if you can't - and most of us can't - then there is a kind of licensed extraction involved.
It has set me thinking about the way governments lend their authority to companies that want to rake money in from us.
There is a long tradition of this kind of thing. The Romans, Columbus and the Conquistadores and the British in India all forced the discipline of working hours on their new subjects by taxing them - so that they had to work to earn the money.
This is a form of slavery, and - although I'm not accusing the education authorities of enslaving parents - it is a related form of abuse.
It is related also to the way that local authorities used to hand us over to the tender mercies of private clampers, allowed to extract almost whatever they liked. This was also a kind of licensed extortion, and I'm not sure that forcing parents into the higher price brackets - allowing the travel industry to put a premium on fares outside term-time - is that different.
But the reason I've been thinking along these lines is that I have just read the most terrifying article in the American magazine The Nation, about an extreme version of this phenomenon. It involves handing over poor people accused of minor offences to private companies, who then charge them for their own imprisonment and probation.
They charge them so much, in fact, that they can never pay off the debts. It is a kind of peonage and, although the abuses by a probation company called JCS in Harpersville, Alabama, have been struck down by a local judge (he called it a "judicially sanctioned extortion racket"), similar abuses are going on in other parts of the USA.
This is how the article ends:
"Meanwhile, even as the Harpersville case wound its way through the courts, a prison healthcare corporation called Correctional Healthcare Companies bought JCS, allowing its new parent company to expand into the supervision and enforcement industry. And six months after Judge Harrington’s ruling, GTCR, a Chicago-based private equity firm, bought Correctional Healthcare Companies, including its wholly owned subsidiary JCS. It was a sign that the finance world believed criminal justice would remain good business..."
It is also a sign that the new kind of narrow efficiency practiced by the finance and private equity companies is quite happy to involve peonage if the option is open to them.
But this isn't just about privatised services; the link between state schools and travel costs is another example of the state holding us down while someone - public or private - rifles our pockets.
It is now a century since Hilaire Belloc and G. K. Chesterton claimed that both capitalism and socialism would tend towards slavery. It increasingly looks as though they were right.