I'd say that I'm fairly opposed to protectionism in general, and I'd go along with Chris's position (that Shuggy amplifies well in the comments).
Two questions though.
Firstly, should there be a cultural exception to this general principle? I'd have no objection to Asian countries having a comparative advantage in, say, rice - to use an obvious example. But the US has a large, prosperous, consumerist marketplace for audiovisual content. It's a marketplace that even largely shares a common language, and one that some would say has the ability to use subtle forms of conditioning to overcome some rational choices that consumers may otherwise make. They have a comparitive advantage, and it's hard to distinguish between their approach to foreign markets and the traditional pre-digital economist's concept of 'dumping'. Should we object to the prospect of TV and cinema being dominated by US exports?
Secondly, are there cultural reasons to see 'comparative advantage' as a form of the 'objectification of Labour' on a grand scale? Whole economies just making t-shirts to use Shuggy's example. Not being a Marxist scholar, I don't have the answer here - but one of the more appealing things that I found in my limited reading of Marx was his critique of the way that mass-production reduced human creativity.
Is there a downside to workers focusing purely in one industry - even if it results in immediate and substantial material improvements in their lives?
I don't know the answer to these questions. I used to think I did though. Any comments?