Drezner daydreams:

Most approaches predict that the living dead would have an unequal effect on different governments. Powerful states would be more likely to withstand an army of flesh-eating ghouls. The plague of the undead would join the roster of threats that disproportionately affect the poorest and weakest countries.

The different international relations theories also provide a much greater variety of possible outcomes than the Hollywood zombie canon. Traditional zombie narratives in film and fiction are quick to get to the apocalypse. The theoretical approaches presented here, however, suggest that in the real world there would be a vigorous policy response to the menace of the living dead. Realism predicts an eventual live-and-let-live arrangement between the undead and everyone else. Liberals predict an imperfect but nevertheless useful counterzombie regime. Neoconservatives see the defeat of the zombie threat after a long, existential struggle. These scenarios suggest that maybe, just maybe, the zombie canon's dominant narrative of human extinction is overstated.

Apparently he's working on a book along these lines.