With the national convention, 50% of the ticket, the Presidential debates and a central campaign theme all set for more relevant newscycles of the future (do you really think Kerry is going to launch a major initiative in the middle of Richard Clarke, Bob Woodward, and prison scandals?), has Kerry been defined already?
I'll tell you what people probably think up to now - he's bizarrely wealthy, he's a heavily-decorated veteran that threw something over a fence once, he's a clunky public speaker, he beat Howard Dean, he's got a full head of hair, he voted against a bunch of defense funds back in the day, and he thinks Bush suffers from incompetence in Iraq.
In other words, people have a vague wash of information about the guy, but none of which adds up to a real narrative picture that "defines" him - despite a crap-load of money spent from the Bush coffers to do so.
Most Americans aren't paying a whole lot of attention to specific policy right now, they are watching the Iraq debacle unfold in a catastrophic fiasco. Which means that while they don't have a real sense of Kerry early on, the once-"defined" Bush as impenetrable commander-in-chief is now becoming a liability for Mr. Mission Accomplished. So much for definitions.
Kerry knows that there is a reason we love sit-coms with unlikely amnesia stories. It's because we can't remember ANYTHING that happened more than a month ago. Who's Paul O'Neill? Ken Lay? Christine Whitman? These names mean something to us, but for most Americans it was a 30 second piece on ABC news four months ago. Remember Kerry fired Jim Jordan? Do you think anyone else remembers, let alone cares?
Kerry will be defined when he starts walking around with the other half of his ticket, when he gives a huge rallying speech after Bill Clinton in his hometown convention, when he unveils his central campaign message according to what is relevant in the late summer.
Until that time, ignore - I know it is difficult - a media that is convinced that people are really, really paying attention to the national campaigns between the primaries and the national conventions.