This is an excellent example of what happens when one allows foreign-policy ideology to influence what is rightly a First Amendment issue. There are a lot of countries that "should" be on the sanctions list, but aren't, due solely to ideology: Their trade-related behavior (and often behavior in everything except calling the US a "friend") is identical to nations that are on The List. Then, too, there's the moronic "thou shalt not correct errors" aspect of the rule, which allows publication only of work that is imported in camera-ready form.
The whole issue of selective trade sanctions leaves a lot to be desired. It's also inconsistent with our obligations under WIPOâ€¦ <SARCASM> but the US would never, ever violate a treaty that it signed, would it? </SARCASM>