Postponing the new Medicare prescription-drug benefit for one year could save the US government $30 billion. Cutting controversial bridges and bikeways from the highway funding bill might reduce spending by $6 billion per year. In the science category, cancelling research on Project Prometheus, slated to develop nuclear reactors for use in space, could eliminate $5 billion over 10 years. As these examples show, it’s easy to find potential cuts to offset Washington’s spending on recovery from hurricane Katrina, as President Bush has vowed to do. A $2.6 trillion annual budget provides lots of targets. But actually making those cuts? That’s another story. One person’s unnecessary program is often vital to another. It’s difficult to save big bucks without infuriating powerful constituencies, such as the elderly, farmers, or the Pentagon.