How much can Labour pledge at election while remaining credible?

Keir Starmer will obviously want to fight the coming year’s election promising change and enthusing voters with his bright ideas – but just how much will the public be expecting him to transform the UK? And how much is actually deliverable in one term when infrastructure and services are in such a parlous state?

Promising sunlit uplands and £350m a week for the NHS worked for the leave campaign in the Brexit referendum, appealing to…