I have a question each for Greens and ALP members.

First, the Greens: back in 1992, when the Australian Greens was formed, is this what you wanted to achieve: emissions excluding land use are roughly 6% above 2005 levels and rising, our Paris target is a joke even before you consider it is based on dodgy accounting, the first mammal to become extinct due to climate change occurred in Australia, and the likelihood of Australia achieving zero net emissions by 2050 is virtually nil?

Would that in any way have been considered a success back in 1992?

Sure, you have some Senate seats. Lovely. But that’s not really how we measure success when the planet is warming, is it?

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So here’s the question – can you honestly say you have done more to combat climate change and reduce emissions by forming your own party than if you had instead channelled your forces into the ALP à la the “progressive caucus” in the Democratic party (which was founded in 1991 and whose first chair was Bernie Sanders)?

At this point I see you roll your eyes: “Oh yes, change from within – we’ve seen how that works!” Except we’ve seen how it works when you are outside the ALP. What if you had been inside?

Yes, you look with hope at the “Green wave” in Europe, but be honest, that is not going to happen here. Not with our voting system and electorates.

What if you had joined a party of government, worked slowly but surely to get numbers in various branches – such as Melbourne or Sydney, an ACT seat or two – taken control of the process for Senate selection in a state or territory so you got your candidate at the top of the ticket?

Can you honestly say you would have achieved less?

The IPA and its slithering brine of libertarians have effectively taken over parts of the Liberal party in this manner – to the point where James Paterson of all people was number 1 on the Liberal party’s Senate ticket in Victoria.

Was it also impossible for you to join a union and indulge in some politics? (And yes, I know the unions and their control over pre-selections is awful).

Heck, the activism would not have needed to stop, but you would have been inside the tent – imagine a left wing of the ALP that actually was leftwing?

Yes, the process would have been slow and frustrating, but ask yourself: just how much of a real influence have you had on climate change policy? How much success have you had?

Is it really a success that after 27 years of the Greens the LNP cares so little about climate change that Scott Morrison can appoint Angus Taylor as minister for reducing emissions?

If that is success, what does failure look like?

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Sure, you might have had to compromise on some of your principles (say, on asylum seekers, but has even that been a success?) but are you a vanity project or do actually want to achieve change? Might it not be nice to be a party of government?

Which bring us to the question for the ALP:

In the past quarter of a century there have been nine elections and your party won a majority of seats in one of them.

One out of nine. ONE!

Is that success? At this point, are you really even a party of government?

Let’s be honest, you suck at winning elections.

What if somewhere in that period you realised these Greens folk are not going away, they actually seem to engage young people quite well and have some policies that not only seem quite exciting but are also the right thing to do?

Do you believe in climate change? I mean, really? Because if so, why do you hedge? You are like a doctor who says smoking kills and then tells the patient maybe to cut down to half a pack a day. No wonder people feel it is easy to believe the whole climate change thing is fake. If it was real, surely you would be a lot more urgent.

Why not have a policy that treats the climate crisis like it is a crisis?

What if at some point in the past 25 years you had been big, bold, brash … like the Greens are on the issue? Should you not have reached out to them and worked with them instead of hoping that going it alone would achieve victory?

What about some sort of coalition with this Greens mob? Not as joined at the hip but something formal, something that when in government had some Greens senators or MPs given some responsibility?

Maybe you should have looked at other aspects of the ALP, such as allowing MPs to cross the floor – I’m sure a few progressive MPs would have liked to be able to do that on data retention and encryption bills. It might have encouraged people to join knowing they can actually use their voice.

And let’s talk about factions. You know who likes factions? Nobody. Sure those factional rules might have served you well in the 1950s and 1960s when you enjoyed 23 straight years in opposition, but is there any evidence they are actually good?

And look at some of your MPs in safe seats – no one knows who they are and they are mostly there due to union-backed support and/or time spent as an advisor. Is this the way to win?

You could have stopped contesting some seats (come on, Bandt is not going to lose) and acknowledge you need the Greens preferences. Maybe instead of hating on them, you should have worked openly with them.

No, it won’t be like the LNP – the Nats compete in seats Liberal MPs only see when visiting their hobby farm or while driving through on the way to the snowfields – the Greens and ALP fight over the same territory, so it is a lot trickier.

But how about joining them in the culture wars fight, because seriously, the ALP in the past decade is the most gutless party in Australian history. Mention national security and the ALP folds (passing laws even when you have serious questions about them!). I mean, you are happy to honour Operation Sovereign Borders in the Australian War Museum. What the hell?

Do you want to be a progressive party or a party pretending to be progressive?

Now sure, it would have annoyed many older members and we might have had to cope with people like Martin Ferguson quitting the party. And well … would that really have been a shame?

You might have to admit to some policy that actually has morals attached to it (say, asylum seekers) – but wouldn’t it be nice to do good policy and actually sell it well?

You might have to give up a ministry or two, but so what – you rarely get the chance to be a minister as it is.

Let’s be honest: by 2022 you will have been in opposition for 20 out of 26 years. That is failure.

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Now of course, none of this is going to happen. The Greens will never think they did wrong (and I am not sure they have), and the ALP will never agree to any sort of coalition with the Greens.

They both hate each other, and their differences are pretty deep.

But here’s the thing: what from the past 25 years gives anyone any belief that the next 25 years are going to be better?

I actually don’t give a stuff about the Greens winning Senate seats, or arguments from the ALP about how they have to win more than 10% than the Greens do.

I care about whether we reduce our emissions. When it comes to climate crisis, that’s the only scoreboard that matters.

Right now, the scoreboard is not a good sight for anyone who hopes to see real action on climate change, and both parties should ask themselves what they are doing to change that.

• Greg Jericho is a Guardian Australia columnist