For it is not the amount of money spent that should be the starting point for the debate, it is a question of what we, the people, believe that government is for. And part of that debate is, are we willing to pay the price for what we want?
It is a debate which has gone unargued for too long, almost entirely because it is an increasingly difficult one. At one end, the focus is on maintaining a welfare state that was never designed to cope with the burdens now placed upon it, one that presumed jobs for most, if not all, one that presumed that most people would be pensioners for relatively short periods. This has led to the creation of a 'client state', reliant on the State for sustenance, as a level of poverty which would have been described as luxury by our grandparents (certainly so in the case of mine). At the other, an assumption that all of those on benefits should just "get off their backsides and find a job", that the State should not play a role in providing a wide range of services, and that tax is something to be minimised using whatever means possible.
Of course, life is more complex than that. Many of us have concluded that the prospect of the poor living on the streets demeans us as a society, we believe that our nation should play a part in making the world a better place, both environmentally and socially. All of this comes with a price tag. We believe that libraries are part of a civilised society, that the elderly should be protected and allowed to live with dignity, that people should not be excluded from opportunity just because they are poor, or disabled, or simply 'not like us'. And that costs too.
So, instead of setting an entirely arbitrary target, perhaps David Laws ought to consider this bigger, more complex question. Because government should be like Goldilocks and the porridge, neither too big nor too small, but just right...