The SNP is the latest party to think it is within the power of the politician to offer a balanced budget. They say in their manifesto that they will:
When will politicians learn about sectoral balances? It's a simple fact that when consumers, business and overseas (via trade and investment) decide they all want to save there is nothing the government can do as a result but run a deficit. That makes this promise by the SNP, and others, economically impossible and any attempt to deliver it something of a suicide note for the economy.
For once, don't take it from me. I'll link to Frances Coppola's version of the story instead.
In the meantime one has to just sigh with a heavy heart about the fact that UK political debate continues to ignore economic reality.