Tuesday's rematch of Barack Obama and Mitt Romney is likely to be their first of two in which the incumbent's record as Commander-in-Chief is going to be a matter of direct debate. If last week's set-to between their running mates is any guide, there will be opportunities and perils for the challenger. It behooves Gov. Romney to maximize the former and minimize the latter if he wants decisively to defeat the President in these mass-audience settings, and in November.
