Truly a bizarre day in politics

Prime Minister Jacinda Ardern yesterday morning said National's ''troubles'' over Jami-Lee Ross were a matter for the party and its leader.

''Thankfully these troubles are ultimately a matter for the Opposition,'' she said. Sensibly, she added: ''No political party is free from these.''

But after what occurred later yesterday she must be thinking her troubles with MPs Clare Curran and Meka Whaitiri are mild. They have not gone rogue as Mr Ross has. While they made mistakes, neither displayed the remarkable and gross disloyalty of Mr Ross, nor his peculiar behaviour.

Any support Mr Ross might have had disappeared with his tweets and his accusations. National prides itself on its discipline, and Mr Ross has displayed none.

He seems determined to go in a blaze. There will not be a single bridge unburned when Mr Ross' time is done.

When he stands as an independent in the safe National seat of Botany in Auckland, the voters are unlikely to see him as a hero but someone lacking in judgement and fidelity. Even if some of his accusations are accurate, the way he has gone about matters leaves him isolated.

He has not only called his leader ''corrupt'', but he apparently secretly recorded at least one conversation with his leader which he says can be used as evidence. Other National MPs must wonder if he did the same with them.

It is hard to see what he hopes to gain other than vengeance. Mr Ross was Mr Bridges' ''numbers man'' in his leadership and a former close colleague. He was rewarded with a relatively senior role for one so young (32), as senior party whip. But some say that he wanted more. Whatever the reasons, he fell out with Mr Bridges and his world has come crashing down.

What happens next, after this weird day in politics, is hard to predict. If, as MP Judith Collins said, Mr Ross is purely ''delusional'' - and this can be the image which sticks, as someone who has completely lost the plot - Mr Bridges might be able to carry on.

However, if there is something to his allegations about donations being fiddled for political purposes - vehemently denied by Mr Bridges - then National will suffer further damage and Mr Bridges is history. Mr Ross' claims go so far as criminal activity, in which he himself took part, even if this is the sort of thing that discreetly goes on. Matters could become really messy.

Mr Bridges says the caucus meeting yesterday did ''draw a line'' under the matter No chance. The best he can hope for is that there is nothing to the claims, that the aftermath of the outbursts fades relatively quickly and that the National Party has no stomach - at least at this stage - to hop on the damaging leadership merry-go-round as Labour did with Phil Goff, David Shearer, David Cunliffe and Andrew Little before Ms Ardern righted the Labour ship just before it hit the rocks ahead of last year's election.

One of the keys, of course, will be National maintaining its poll ratings. Mr Ross is correct that Mr Bridges has failed to connect well with the public. But that matters only so much if party support stays high and, therefore, the jobs of MPs are safe.

Whatever their feelings about Mr Bridges as a longer-term leader, all the caucus had to back him yesterday and show unity. If some had not, the extraordinary day would have turned truly toxic.

What started as an inquiry into leaked expenses, due to be published three days later anyway, lurched to a climax yesterday. Even experienced political commentators seem bamboozled by the unprecedented kamikaze actions of Mr Ross.

The question now is whether he takes Mr Bridges down with him, and how much damage is inflicted on his former party.