The Carr that skittled Kevin

Appointing Bob Carr as foreign minister-designate – ahead of the New South Wales parliament formally electing him to the vacancy caused by the unexpected departure of no longer faceless man Mark Arbib – may be just what Prime Minister Julia Gillard needed as a circuit-breaker.

There are certainly signs the Liberal opposition thinks so (along with such parts of the National Party as are able to think further than the brims of their hats); its confected incandescence over the Rudd non-coup and Labor brawling show that very clearly.

Two things emerge immediately from the Carr appointment. The first is that Gillard has finally (albeit messily as usual) stamped her authority as leader on something of moment. Many commentators have already noted this. The second is that Carr neutralises – though neuters may be the better term – Rudd as an alternative foreign affairs voice, again something that other commentators have noted. Both these outcomes are beneficial for Gillard and Labor. It remains to be seen whether benefit then flows on to governance or indeed to Australia's foreign representation.

It is in the chaotic workings of the law of unintended consequences, however, that longer-term questions arise over the events of the past week. Tony Abbott's charge for The Lodge 2013 has not yet been officially dented – we'll have to see several sequential opinion polls for any real assessment there – but there's no denying that a working Labor government would claw things back to a very contestable margin at the next election.

Gillard's image is tarnished. The manner of her 2010 coup against Rudd, his devious behaviour and disloyalty since, and the marginal outcome of the 2011 election, would have taken the shine off any prime minister. The fact that until now Gillard has looked like a leader only by power-dressing – overcooked events at the Lobby restaurant in Canberra on Australia Day aside – hasn't helped.

Rudd has now been very effectively sidelined. Well, no: actually he sidelined himself, the victim of his own unbridled hubris and self-image. He won't be back in the medium term, if ever. The drubbing he got last week speaks volumes. If there's a future challenger this term, it's unlikely to be him. He may remain the member for Griffith. But as that old scoundrel Graham Richardson said during the week on Sky TV – who cares what Rudd thinks; and he might usefully have added, or does.

If Gillard does get her act together the focus will rightly turn onto Abbott and his credentials as alternative Australian prime minister. Other than for agenda-setters on The Australian newspaper and some of the tabloid TV channels, this is where it should be.

It is not true to say – as Labor trolls in the all-pervasive social media continuously assert – that Abbott is unfit to govern. He does have policies (some of them are execrable but that's another issue, especially for traditional small-l Liberals) and he does have a working team. It would be folly to assume an incoming Liberal-National government would be train-wreckers in disguise. That's just what people on opposite sides in politics say about each other.

Labor hasn't been a wrecker in office since 2007 (well Rudd was, but he is now his own problem) and no one able to see out of the political prism would suggest it has. It hasn't been very good at governing, but – again – that was a situation wrought upon Labor by the 2010 election. Bob Brown's a pleasant fellow, but he's never easy to work with and he has his own politics to consider – continuing to grow the Green vote. The independents are relevant only on the numbers in the present parliament. A fresh election, in all the new circumstances, might well sort them out.

Abbott articulates an argument that is specifically designed for opposition. He does it very well, although he's had a lot of stumble-footed help from the government to push along his argument that Labor's a dog. That's essentially his job, until an election comes along and he has to say what he'll do instead of just what the other side should do. It's worked for him as leader, in the opinion polls. But effectively they don't count, other than as material likely to cause euphoria on one side and indigestion on the other. The reality is that on Election Day – in the only poll that really counts – the margins are likely to be far tighter than public opinion sampling has previously indicated. Abbott knows this as well as anyone.

And that's his real dilemma. If Gillard's a dud – his continual assertion – and remains so, Labor will ultimately fix its own problem. It won't do so by drafting Rudd: he's killed his own chances. If on the other hand Gillard does now actually get it – if she can lead without internal distractions and with the real support of all her colleagues – and public opinion (as gauged) begins to swing Labor's way, Abbott's in trouble.

He's a combative character (he's an engaging one too, in private) with views that he articulates well but which are not necessarily those of a swinging voter, or even of many small-l Liberals. It's not just that his frequent macho war-cry is tedious to most people, or that he and his immigration spokesman Scott Morrison shamelessly beat the jingoistic drum on illegal boat arrivals.