That's not really how it works. Economists are generally pro-trade because it frees up more money in the economy that can now go towards other things. For instance, if Intel can save a million dollars by manufacturing their CPUs in China, that's a million dollars they can now spend on R&D domestically.

Now, of course, that means diddly squat to the factory workers that lose their jobs. And that's why it's important to ensure people who are victim to outsourcing are taken care of in some capacity. That's a much more complex issue, but in general, "saving jobs" isn't in the best interest of a country as a whole (in the long run anyways).

The same will be true once automation becomes a thing. Once we can do things for a fraction of the price and dramatically increase productivity, costs will go way down. Unfortunately, that also comes with massive job loss and we'll have to figure that out as well. But that doesn't mean we shouldn't do it for cheaper.

It's kind of like saying we should have banned cars because horse drivers wouldn't be able to afford goods. The opportunity cost of not using cars to move around people and goods is much greater than the temporary economic distress of the horse drivers.

Keep in mind, this is not a "screw the factory workers" point of view. I'm just saying generally it's better in the long run for nations as a whole to do things for cheaper when they can, so long as the lower costs aren't offset by severe moral hazards.