Remember in the height of the primary season when Howard Dean was at the peak of his popularity? Most people attributed it to the fact that he was willing to take it to Bush on almost every issue: the backbone factor. Kerry needs a serious dose of Backbone Factor right now on national security.
As expected, BC04 and the Republicans have tried to paint Kerry with the inevitable "soft on defense" label used on every Democratic presidential candidate in my lifetime (goes back to Carter; yes, I'm a youngin'). And it seems to be working. Bush is favored on security/terrorism by 2:1.
Kerry needs to take the fight to Bush on this very issue and needs a better message than "Well, of course I'm better on defense, I served in the military."
Kerry needs to hammer EVERY DAY the reasons why we're not safer as a result of Bush policies. Leave the Iraq war be for now. Focus on domestic security priorities like cargo container inspection (this was part of every speech Dean ever delivered), underfunding of Homeland Security, pulling National Guard off of the Golden Gate Bridge b/c of other budgeting priorities (i.e. Iraq).
Kerry needs to take the offensive. "I'm a Vietnam vet and he's not" is not going to cut it. Trying to shift the focus to the economy is not going to cut it (2002, anyone?). Whatever anybody tells you, this election will be won by whomever makes Americans feel they will be safer. Pure and simple. We can try to shift the focus all we want, but "It's the economy, stupid" does not apply in wartime.
Hammer Bush on domestic security every day. Come up with a cool, two- or three-word catch phrase like the Republicans manage to come up with for almost any issue (e.g. death tax, partial-birth abortion, investor class, etc..). Take the fight to Bush every single day, otherwise Kerry's national security message is going to get pigeonholed by the media as, simply, "Vote for me, I'm a veteran and the other guy isn't." The American people need something more concrete.