It's called "safety factor": Most civil engineering is done with the help of generous "safety factors" -- protective margins of error in our calculations, designed to make sure we're not running too close to danger.
Most people don't realize how hard we're leaning on the safety factors that previous generations engineered into our infrastructure. Just take a look at the condition of old bridges everywhere, like this one:
I happen to work day-to-day in the infrastructure field, and it also means I spend a lot of time traveling -- so I end up seeing a lot of infrastructure up-close. Sure, there are plenty of places where things are shiny and new.
But all too often, the things that keep America running smoothly are being held together with chewing gum and baling wire, as the saying goes. And the people tasked with keeping things working are all too often given impossible duties -- like keeping things in good working order without adequate maintenance budgets.
It's such a big problem that I've given the same talk several times to public-works audiences on this very topic:
I'm in favor of low taxes and small government about as much as the next person. But I also know that you can't have a functioning economy without the infrastructure necessary to support it. So, in place of an agenda driven strictly by cutting taxes for their own sake, I propose the following:
Decide what you want, limit your wants as much as possible, and pay for everything in full.
Should that really be controversial at all?