It’s that “entirely” that I don’t buy. Yes, pure realpolitik considerations enter into which terrorist organizations are labeled as such and which are not, and which groups the U.S. government works with and which it tries to marginalize. But so do other considerations – including not only ethnic, cultural and religious affinities (and the activity, yes, of domestic pressure groups), but moral considerations as well, and the extent to which the aims and deeds of a given insurrection can be read as being in consonance with American principles.
At the risk of beating this issue into the ground, I have just a couple more points. It might be going too far to say that the official government attitude of the government toward the enemies of another state always depends entirely on the state of relations between the U.S. and that state, but in most cases I would say that it does depend entirely on those relations. The Irish republican example shows that there can be some significant domestic political pressure that works against support for the interests of an ally, but even so relations with an allied state usually win out. Conversely, when groups that we would otherwise normally consider as threats (be they narcotraffickers, terrorists or some combination of the two) prove useful as proxies against pariah states we see Washington adopt their cause or at least provide them with support–the use of Jund’ullah against Iran makes no sense if you assume that Washington always opposes brutal, Islamic fundamentalist terrorists.
Then there are other cases where significant domestic political pressure drives official policy towards a certain pariah state, such as Cuba, and provides a cloak of protection to those suspected of committing terrorist acts against citizens of the pariah state. I will grant that there are some terrorists who may be more easily romanticized as “freedom fighters” than others. European and Latin American militants who draw on the rhetoric of Western revolution are more effective at pushing the right buttons than are Islamists, who tend to cast their struggle in what is for us a largely alien idiom. That being said, it seems to me that if we were able to romanticize Pashtun warlords and their ISI paymasters into freedom fighters against communism there is scarcely any limit to the kinds of groups who can be re-made into the champions of liberty.
Would a majority of Americans sympathize with such groups in the absence of official government support and a steady drumbeat of negative media coverage portraying the groups’ enemies as embodiments of evil? Probably not, because most Americans would normally not be bothered by such conflicts without constantly being prodded and pushed to take sides. There would always be some degree of support for old proxies that Washington has abandoned (until Savimbi died, there were still plenty of old Cold Warriors who were ready to praise him and his fight against the Marxists in Angola), and there will always be ideological or religious enthusiasts who will rally to the cause of militant groups overseas. Just as the Sandinistas became a fashionable group to defend on the left, and the SPLA became a cause celebre of evangelicals, there will always be some number of Americans interested in advocating for some rather nasty groups for their own reasons or out of some naive identification with their cause. If there are enough sympathizers, as there were in the Irish republican case, it will have an effect on policy, or the sympathizers’ views may align with the official policy that an exile community has pressured the state to perpetuate (as in the case of Cuba). For the most part, however, what will drive state policy towards an individual terrorist or terrorist group is the relationship between our government and the government of the country in question.
Update: Matt Duss joins the discussion with a good post in which he makes a similar argument to mine.