Rust cost’s the world a staggering US $2.2 trillion a year*, which is over 3% of the world's GDP. Surprisingly, neither industry nor governments seem to put it high on the agenda except in safety-critical areas such as pipelines and Aerospace.
In theory the solution is easy - anti-corrosion coatings. Unfortunately not all of these work as well as they should, most prevent reactions with liquid water but allow water-vapour and oxygen, to seep through and react. Perhaps people just are a little rusty with testing!