Considering the decimation of the manufacturing base here in the USA, I shudder to think what would happen were we required to make war on the scale of the previous World Wars.
Virtually all our electronics are made somewhere else. We can't even build our own infrastructure[0]. Who will build the Liberty Ships[1]?
As long as we don't forget how to do everything, we can ramp manufacturing back up quickly. Currently there are manufacturing plants pumping out aircraft, tanks, ships, and munitions at a slow rate. They are limited by money and lack of demand, not by the ability of the manufacturing plants to pump out more. If suddenly we needed to double or triple capacity you bring in more people and machines to do the work, but the process is in place.
But if we stop building - even for a few years - we will lose all that and be back at square 1. This is why the Navy has a huge number of aircraft carriers. We don't need that many really, but if we stopped producing them we would lose all the institutional knowledge and experience. So they dribble one out every 5 or 6 years so that lots of people are constantly working on it.
That will not happen again. It is a bygone era. Now it will either be country to country attacks (Iraq, Afghanistan, Vietnam) or full blown nuclear wipe-out. In either case protecting Cleveland won't make much of a difference.
We manufactured more in 2009 than Germany, Japan, Italy and the U.K. combined. China's growing fast, but we're still outputting something like 40% more.
Virtually all our electronics are made somewhere else. We can't even build our own infrastructure[0]. Who will build the Liberty Ships[1]?
[0]http://www.nytimes.com/2011/06/26/business/global/26bridge.h...
[1]http://en.wikipedia.org/wiki/Liberty_ship