Maybe the heat has gotten to them: a prominent IR prof/blogger (Drezner) and a prominent writer/blogger (Mead) have a go-round about a so-called "theory" promulgated by a prominent ... well, whatever Friedman is (careful, no bad words allowed). Drezner is basically right, but I don't know why he's wasting his time on this in the first place. He suggests that a kernel can be salvaged from the Friedman "theory" because two countries with McDonald's, although they can go to war (see his examples), may be less likely to do so. He then proceeds to admit that this proposition, even if true, is not useful because the presence of McDonald's is an "intervening variable." He nonetheless urges some student to write a thesis testing the 'war-is-less-likely-between-countries-with-McDonald's' proposition.
However, 'traditional' interstate war (country A fighting country B, without the complicating presence of any internal armed conflict) is so rare these days that the proposed test is, IMO, of minimal interest. Friedman's "theory" is not a theory and Drezner's weaker version of it is a waste of time, virtually by his own admission. I blame John Sides for drawing my attention to Drezner's post: it's all the fault of someone who doesn't even study international relations. Figures.