When budgets are set in business or government, the traditional method is to start with the previous budget for a particular activity or department, treat it as the baseline and then agree an appropriate percentage variation (which is usually upwards).

There is, however, an alternative method called zero-based budgeting, in which the historical baseline in disregarded and every line item has to be justified or reduced to zero. It is, in theory, a much more robust approach to controlling expenditure – and one that allows a fundamental rethink of the very purpose of government in the 21st century.

In a deliberately provocative article for The Week, Pascal-Emmanuel Gobry invites us to consider a rather unusual zero-based budgeting scenario:

“Imagine that omnipotent space aliens from the planet Zyrglax land on Earth and take control of the United States. But these aliens are somewhat bizarre, and they change only one thing: they… prohibit the government from any action or law providing for public education, even ruling out school vouchers and the like. All school budgets are rebated back to the taxpayer. Failure to comply will result in America being blasted to dust from orbit.”

Do these aliens work for the TaxPayers’ Alliance? Gobry leaves us guessing as to the motive for their intervention in human affairs, but he does speculate as to the consequences:

“…at first it would be chaos. Millions of kids would be out of school, parents would be helpless, and so on.”

But far from resulting in the collapse of civilisation, Gobry reckons that society would soon adapt:

“For the upper class, not much would change — except for a handful of magnet public schools, they’ve basically opted out of the public education system.”

Then he turns to the middle classes:

“This is where things get interesting. For one, a lot of people would smell a great business opportunity. Average private school tuition in the U.S. was $8,549 per year in 2010. Catholic schools manage to get it down to $6,018, and to $4,944 for elementary. For a middle-class family making $50,000 a year, putting your kids in private school would be a sacrifice, but it would be doable.”

And for those on lower incomes?

“What will happen is that philanthropy will take over… More than 100 people have signed [Bill] Gates and [Warren] Buffett’s ‘Giving Pledge,’ getting billionaires to agree to donate more than half of their wealth to charity. And the most popular charitable cause among hedge fund titans is education.”

One suspects that the charitable provision of schooling for the poor would be patchy at best. And even among those in the middle, the children of parents who care less about education would be at a disadvantage to those of parents who care more.

But here’s the thing: a lot of this already applies to the state education system. Home environment has a much bigger impact on educational outcomes than anything that happens at school. Furthermore, the average attainment gap between children from richer and poorer backgrounds gets wider not narrower over the years they spend in school.

None of this is to suggest that we should, in fact, eliminate the education budget. Rather what we ought to do is ask some very hard questions as to what does – and doesn’t – make a difference in our schools.

We then need to ask if at least some of those resources could be used to make a bigger difference to children’s life chances in another way.