I've previously noted the glaring contradiction among neoconservatives, whereby they simultaneously (a) tell American Jewish voters to vote Republican because (they claim) the GOP is better for Israel and (b) insist that it's anti-Semitic to point out that some are guided by their allegiance to Israel when forming their political beliefs about U.S. policy. Obviously, anyone who does (a) is, by logical necessity, endorsing the very premise in (b) which they want (when it suits them) to label anti-Semitic. Neoconservatives constantly make political appeals to Jewish voters expressly grounded in the premise that American Jews are guided by allegiance to Israel (vote Republican because it's better for Israel), yet then scream "anti-Semite" at anyone who points this out. When faced with this glaring contradiction, their typical response -- as illustratively voiced by Commentary's Jennifer Rubin, after she argued in a 2008 Jerusalem Post column that American Jews should vote against Obama because he'd be bad for Israel -- is to deny that "that the interests of the U.S. and Israel are antithetical" and insist that "support for Israel in no way requires sacrificing one’s concerns for America’s interests." In other words: to advocate for Israel is to advocate for the U.S. because their interests are wholly indistinguishable, even synonymous. [internal hyperlinks omitted]
Now, I think I've sufficiently registered my displeasure at the notion that Jews are single-issue voters whose vote can be grabbed based on whomever runs to the most hawkish position possible on the Israeli-Palestinian conflict. It's deeply patronizing to begin with, and clearly doesn't match either Jewish political behavior nor expressed Jewish preferences regarding the conflict; yet, instead of re-evaluating what it would take to get Jewish votes, Republican operatives just moan louder and louder that we're crazy. So yes, that annoys the hell out of me.
Nonetheless, I think this dual loyalty argument needs some interrogation. Specifically, what does it mean to have dual loyalty?
The general definition I read is that one has conflicting loyalties when one is willing to prioritize the interests of another nation over ones own. So I constantly read folks saying how the US supporting Israel clearly isn't in America's interest, because it has this effect on our budget or that effect on our other foreign policy priorities in the region or the other effect on our general national security posture. Implicit in all of this is a pretty narrow, generally neo-realist (think Walt and Mearsheimer), understanding of what "American interests" are. Neo-realists would hold that nations are only interested in maintaining and augmenting their national security posture; because the structure of the international system is anarchic, states cannot trust one another and must perpetually behave defensively.
I don't entirely reject this outlook, but I think that it is typically taken too far and doesn't match actual state behavior. And particularly for a hegemon like the United States, it really doesn't make sense. To say the United States must adopt its foreign policy towards Trinidad and Tobago with an eye towards minimizing security threats simply defies belief. States want security, yes, but states want lots of other things as well: prosperity, cultural interchange, and moral progress, to name a few. And, as we might expect, these values are often contested -- what is in "America's interest" depends greatly on moral priors which can and are disputed; in most cases, to say "you're not behaving in America's interest" is to say "you're not behaving in my conception of America's interest". So long as one is putting forward a good faith vision of what the American project should be, I don't think it makes sense to accuse them of failing to be loyal to America. Fool-hardy, perhaps, but not disloyal.
And I do think such a conceptualization of pursuing the American interest can encompass urging policies which help another nation. Let's say the United States was considering adopting a policy which would simply gratuitously hurt Greece. I think a citizen would be perfectly justified in opposing it; it is quite reasonable to conceptualize American interests in such a way so as to not be vicious to other countries for no reason (I also would expect Greek-Americans to be more vocal in their opposition -- something I see no problem with. Greek-Americans have the same right as everyone else to promote their own conception of the national interest). Even if we modify the hypothetical so that the policy was not "gratuitous", but instead was just financially exploitative: suppose Wall Street had an opportunity to loot Greece blind, sending billions of assets into our borders. Once again, I don't think "loyalty to America" requires one to support the action. Mutual international prosperity can be an American interest. And once we accept that, we can accept anything as at least potentially in America's interest, because that category is something that gets developed through a process of democratic deliberation -- it doesn't exist in the ether waiting to be plucked out by Salon columnists and Harvard neo-realists.
The point is that these appeals to "American interests" (and this is hardly the only context in which they pop up -- including, often, assertions that folks opposed to the prevailing wisdom regarding the American/Israeli relationship are hostile to American interests) almost always take as a given a static conception of what American interests are that is usually the very thing under dispute. By fiating that conflict away, they can then cast their opponents out of the realm of true citizenry. I don't think the move is legitimate.
So is there such thing as "dual loyalties"? I can think of two examples, neither of which describes what pro-Israel Americans are doing. The clearest example is when someone simply does not see themselves, in good faith, as pursuing a project that is in the American interest. Often times, people don't -- I doubt the American al-Qaeda terrorists think they're doing what they're doing for the ultimate good of America (even if they think that it is ultimately good for the people of America). Loyalty in this case means loyalty to the sovereign. Second, I think one could argue that pursuing benefits for an extraterritorial body in a way that runs contrary to domestic law is an example of dual loyalty. I'm not actually convinced of this, because I really think that loyalty is a state of mind, and if a person truly believes their acts are good for America even if they breach the law, I'm not sure loyalty is the block I'd hang them from. Nonetheless, it is a little semantic, since I have no qualms about saying such a person can be punished for their malfeasance. And since I think that loyalty to a country does provide at least a general duty to obey the sovereign, I don't feel that uncomfortable with this formulation (though consider the age old movie plot where the hero has to deliver some secret to the enemy that reveals domestic treachery in order to stop the war which would destroy America).