It’s nearly gasp-inducing to see Foreign Affairs and Humanities Professor Walter Russell Mead’s headline, “Have We Gone From a Post-War to a Pre-War World?” (Via Instapundit.) As the United States prepared its response to 9/11/01, the sense was palpable, in certain quarters, that any sort of actual war was objectionable mainly on the grounds that we were in a post-war world in which all differences could be resolved without organized violence on that scale.  It wasn’t just that that war was unnecessary, but that all war had been rendered unnecessary by diplomacy and technology.

And yet, here we are:

… it is possible that other powers may not be sure how committed the United States is to defending its allies or its interests around the world, and that can make bold or even rash moves look attractive.

It’s possible, for example, that some people in the Chinese leadership look at President Obama’s mixed messages about his “red lines” in Syria and wonder how seriously to take American red lines in the Pacific. … Russia and Iran may be asking themselves similar questions and looking for places where they can push against what they see as weak spots in the U.S. alliance system. At the same time, countries that depend on U.S. guarantees (like Israel and Japan) may become more aggressive to deter potential adversaries.

Mead’s analysis — comparing the global circumstances leading to WWI with the present day — is nothing if not balanced, and he doesn’t downplay the significant differences between the eras, in terms of the players and their alliances and capabilities.  Still, he notes, many of the differences are unpredictable.  Pre-WWI, transportation timetables forced escalation, as no power could delay its decisions and allow opposition to amass forces in exposed areas.  Preparation for potential war thus became akin to an act of war in its effect on decisions.  High-tech may be similar.

One variable that Mead does not mention, but that worries me, is that the golden opportunity that the Obama presidency presents to enemies and competitors will not last forever.  On a predetermined timetable, his authority will end, meaning that global powers have a deadline by which to decide what position they want to be in when the people of the United States place another — probably (hopefully) stronger and more competent — person in that role.