Productivity and Employment

Scrivener has some interesting comments on the fact that manufacturing jobs are down globally, not just in the US. This is not due to the fact that we are exporting our jobs (as many on the left complain) to Mars or some other extraterrerestrial competitor, but simply because productivity gains allow us to produce more goods with less labor. Whenever someone laments the loss of "good jobs" in manufacturing, I like to point out the fact that only a little over a century ago 90% of American were employed in agriculture, now it is around 3%. While obviously the people who had to move off of farms into cities were stressed by the change, does this mean that we should have banned the use of tractors and fertilizer in order to save those "good jobs".? Just look at the percentage of population engaged in agriculture. Uganda is at 97%, the US is at just 3%, does that mean that we should lament the loss of all those good farming jobs to Uganda?