Labor has been damaged by the leak of Cabinet proceedings, no doubt. Whether the damage is significant depends on how many more there are and how much life the story gets beyond Canberra. The last big bombshell lobbed by Laurie Oakes exploded with a sound like the crack of doom but appeared to interest punters in the real world not a jot. Tony Abbott’s curious decision to announce a business tax cut today might mean the campaign simply resumes as it was proceeding before last night.

The Press Gallery is fascinated by Cabinet leaks, because it allows journalists to portray governments as racked with division when they are simply doing what you’d think they should do — aggressively debate policy proposals. Many journalists appear unaware that Cabinet submissions actually have an entire section devoted to other ministers’ departments commenting on, and frequently bagging the hell out of, the submission being served up for consideration.

But this isn’t your usual Cabinet leak. This is a leak of the discussion that went on in the room when Strategic Priorities and Budget Committee considered paid parental leave and the pension increase; a leak designed specifically to undermine Julia Gillard and, ultimately, Labor’s re-election chances.

The great Labor tradition, that your real enemies are inside the party and not across the aisle, lives on.

If nothing else, at least it enlivened Julia Gillard, who came out with a strong performance this morning in Adelaide to make her intense scrutiny of big-spending proposals a virtue, declaring that she would always be subjecting spending proposals to rigorous questioning, and specifically denying the most damaging claim, that she opposed the pension rise because pensioners don’t vote for Labor (if she did say it, she’d be right, of course — Labor could shower the oldies in $100 bills and they’d still vote en masse for the party of Menzies).

There seems to be Gallery unanimity that it was her best performance of the campaign and, hopefully, a harbinger of a Gillard less like the Mogadoned version of the last week and more like the aggressive performer we’re used to in Parliament. That would run contrary to Labor’s campaign strategy to keep the election campaign off the radar of most voters, but with any luck that may now be abandoned as the polls tighten up — which they are already doing.

It’s not Gillard’s performance in response to the leaks that is the issue, though; this is about her performance in removing Kevin Rudd a month ago, and the continuing ramifications of that.

Clearly the leaker, having failed to derail Gillard with revelations about the leadership non-deal, has had another go. No reason why they wouldn’t stop if this new one doesn’t work.