There are three schools of thought that i've seen.
The first school of thought comes from businesses that engage in it. They see it as a way to cut costs, and don't care about the side effects. They look at the bottom line and stock value. That's the ugly underbelly of capitalism.
The second school of thought comes from certain business analysts. I have seen glowing writeups from them that claim that there will be a "wraparound" effect where the money we are spending in foreign countries will allow those countries to do more business with the US. This may be true; I understand that some of the larger indian consulting companies are now shopping to buy certain US companies in order to expand their presence in the US
The third school of thought of course comes from the people being directly displaced by this activity or whose industry is being affected by it.
I see it as an artifact of the "global economy" and currently as a bad effect on the US economy. People losing jobs or working for less generate less tax dollars for the government and have less money to spend. The US economy, after all, does run on consumer spending.
I also see a "resource drain" as the US moves it's crown jewels offshore; namely manufacturing and engineering jobs & know-how. I see the US weakening it's own economy by exporting these resources to other countries and creating competition from those we've enabled. And they can do it cheaper than we can. It started with manufacturing in the 60's and now it's in full swing with white collar jobs.
This mainly impacts the middle class. I see people in the middle class being slowly squeezed lower and lower on the totem pole as they lose high paying jobs and are forced to take lesser paying jobs.
The key to surviving this for the middle class person is going to be education and ambition. Gone are the days where a person could easily get a great paying job with just a hgh school education.