Heather du Plessis-Allan: Judith Collins is the right person for the job, for now at least

It's already a hashtag. And quite rightly, because Judith Collins really is the woman for the job. #TeamCrusher

A week ago I would never have said that. I would've told you Crusher was too intimidating. Too fierce. Too right wing. Too tarnished.

But, in one way or another, each of those things either doesn't matter, or are exactly why she should be elected leader of the National Party.

Judith Collins may be the only person in National capable of knocking holes in Labour's biggest asset: Prime Minister Jacinda Ardern.

The Prime Minister's greatest attribute is that she is nice. More than that, she's the nicest. No one can out-nice her. She's nice, her partner is nice, her baby will be nice. She's so nice, she's managed to forge a whole political career without actually doing anything. No, really. What has she done?

In the face of criticism, Ardern just says nice, reassuring things that sound like answers and thus cruises through.

Collins is possibly the only National MP with the skills to bloody the PM's political nose. She has the aptitude and the attitude for the job. She can get dirty. She can be mean. She can do low blows and cutting comments while smiling like it didn't just happen.

But — and it's a big but — if she does knock the PM around, she'll never be forgiven for it. Mean girls earn respect, but never love. Collins may make enough crucial dents in the public's regard for the PM, but she'll suffer for it.

So, electing Collins must come with the understanding that this is a fixed-term contract. Once Collins has done her work, she'll need to stand aside. She'll need to be a martyr for her party. The political equivalent of Hodor in Game of Thrones, Leo in Titanic, Jesus in the Bible.

Martyrdom has to happen because (even if Collins doesn't want to play ball and take one for the team) history would say she has a slim chance of becoming the next National Party Prime Minister. Not just her, but anyone who takes over from Bill English. It rarely goes well for the leader who takes over immediately after a party is tossed out of government. Think Mike Moore taking over after Labour's defeat in the early 90s, Bill English giving it a go with National in the early 2000s, Phil Goff failing for Labour later that decade.

History tells us that following an election defeat, there's usually a period of upheaval and then reconsolidation.

So whoever takes over in the next fortnight shouldn't really be judged on whether they'll make a good Prime Minister, because chances are they won't be a Prime Minister. They should instead be judged on whether they'll make a good Opposition leader. National should pick the person most likely to take chunks out of Ardern.

But, I wouldn't put my money on National picking correctly. Two reasons. First, unlike Labour, National's MPs pick their leader. And they're probably — and rightly — wary of Collins. She's known for playing dirty. She's not the most popular figure in the party.

Second, politics is a synonym for ambition. If Amy Adams really wanted to be the next National Party PM she would be wise to let someone else deal with the anticipated upheaval, then take the glory. But, ambition.

And ambition clouds reason.

Ambition would likely ultimately be Crusher's problem if she got the job. If she took hold of the leadership, do you see her letting go without a fight?

She is like an attack dog. She might be great at bringing home the kill, but it'd be a bitch getting those jaws loose again.

• Heather du Plessis-Allan is on NewstalkZB Wellington, weekday mornings