Now Barack Obama says “Iran is a grave threat.” Several points are in order. Rule one (after “Don’t announce a withdrawal date to the enemy while at war”) of national security policy: be consistent. In the course of twenty-four hours, Obama went from “tiny” to “grave” in his Iran threat assessment. His supporters swear he has gone from unconditional, presidential talks with rogue state leaders to something else. (His supporters may wish it were so, but there is little evidence from the candidate himself of this transformation. If there has been, Hillary Clinton gets a big “I told you so.”)

Second, Monday was another day spent on foreign policy and another one with Obama on the defensive. So score one for the McCain messaging team. If every day between now and Election Day is about appeasement, Obama’s foreign policy flip flops and Iran, McCain will be delighted. (And, no, it won’t happen — which remains a problem for the McCain team which is never so effective as when battling on foreign policy grounds.)

Finally, one of the downsides for Democrats of their endless primary season is that the shift from base-directed rhetoric (“I am not afraid to talk to Iran”) to general election moderation (“Of course we don’t talk to our enemies without ‘preparation'”) does not get blurred in the passage of time. Little wonder then that John McCain’s Saturday Night Live appearance featured a plea for the Democrats to keep at it.