Lord Keynes famously said that paying people to dig holes and fill them back up was necessary for recovery. His disciple Paul Krugman wants Martians to attack earth so that we can spur the economy via war spending.
Read the above NY Times report, if you have a strong enough stomach. Keynes would have applauded the Irish housing boom, and von Mises would have explained that such malinvestment leads to bankruptcy and poverty. I would add that it leads to despair, as the wealth, hopes, and dreams of hard working people are shattered.