Headlines have focused on headroom and tax rises. But the root cause of the difficult choices is debt that is now around 100 per cent of GDP. A large government debt can be managed if the economy is growing and interest rates are low. Unfortunately, Rachel Reeves and I are the first chancellors in modern times to have to deal with the opposite: low growth and high interest rates. Unless there is a plan to deal with that debt, Budgets will continue to be a nightmare.