Change is good, even if it causes temporary dislocation.
It's important to measure success not as a number of jobs, but as an improvement in standard of living. Even with 7.9% unemployment, even with what some claim is an increasing income gap and/or stagnating "middle class" income levels, our standard of living remains high. There is no real poverty in the U.S. as people have all the food they need, and many have cars, air conditioning, etc. (ALL have cell phones!) Many of the presently unemployed would not have been seeking jobs prior to the 2nd World War, as you point out.
What we need is not inflation (causing the stagnating income) but a strong currency, so we can enjoy the fruits of our labor.