There is no wonder that the NHS has overspent because the funding model is mathematically dysfunctional. The problem is obvious. You cannot provide an infinite service with a finite budget. In other words the more patients it helps and who come through its doors, the less it has to spend on each of them. Imagine giving the big supermarkets a fixed budget and telling them to feed the nation for free. Nobody would starve but there would be waiting lists for Marmite.
To run a modern, up to date healthcare system which can offer timely treatment and care to everyone who needs it whenever that need arises, requires funding which expands with demand and is driven by demand alone. Yes there can be a framework and there can be restrictions on quasi-medical services which are more cosmetic than cure. But it cannot be the case that genuine demand restricts supply, causing waiting lists and backlogs as well as over complex management structures, leading to failures and overspend of the type we are now seeing.
Some countries use a part insured or fully insured financial model. We could go that way, but it would be a vote loser because the public prefer direct funding by taxation. That is fine but the taxation formula employed must be fit for purpose and expand to meet increasing costs and demand. The public, which means voters of every party loyalty or none, value the NHS more than any other service in the country. For too long there has been a myth that this is somehow free. It is not and moreover it is expensive to do it properly. Abolition of the irrational quango management system with its Foundations, Trusts and Commissioning Boards would help, as well as banning the iniquity of NHS doctors moonlighting into private practice. But the NHS is still going to cost. A lot. And the taxpayer has to foot the bill. Time for the government and all parties aspiring to replace it, to come clean about that.