Liam Byrne: "There's no money left!"
They seem to have noticed that the government pays out the £24bn every year and this money just siphons off into the pockets of landlords, both public and private. If they used it to build instead they would end up with something tangible to show for it.
If public land were used that money could pay for a quarter of a million very nice houses to be built. Then the HB claimants could just live in them free of charge!
One slight problem that might have escaped Liam is that there are actually 5 million households claiming HB. So if his cunning plan were put into action then 0.25m families would have nice houses and the other 4.75m would be homeless. Oops! Back to the drawing board Liam.