I think the most cogent (and only) argument for nationalistic job protectionism is the fact that others are doing the same thing. If other countries are reluctant to export their jobs to you, you would obviously avoid exporting jobs to them in the vain effort to keep employment in your country alive.

I do agree though - I dislike the "Buy American" argument. Other countries are out-doing us in many industries; instead of pledging allegiance to buying inferior goods and services, we really should be fighting back by innovating and simply making our stuff better.