Be careful what you wish for.

The government has now committed to buying a gaggle of nuclear submarines that are 20 or 30 years off delivery and largely uncosted (not less than $100 billion, but after that the sky's the limit). That's foresight for you.

And am I satisfied?

Well, call me a carping old flip-flopper, but no. They're fighting the wrong war in the wrong way in the wrong place.

These submarines won't be docking for at least 25 years, and they have at least a 50-year life.

That means we have to predict what we'll be using them for until 2095.

Imagine that Britain had begun designing the Spitfire in 1865 for use in 1940 and you'll have some idea of the degree of difficulty involved.

On the purely military front, we'd be better able to damage Chinese capacities if we spent that $100-and-something-billion on developing a robust computer hacking culture, or perhaps some nasty drones.

On the purely military front, too, submarines or no submarines, our chances against China, which by 2050 will have a military superior to that of the US, are not encouraging.

By themselves, though, purely military considerations don't have much relationship to struggles between nations.

If we want to stand tall, we'd be much better to throw the money into quantum computing or new battery technology - something that has industrial spin-offs to help us grow the economy and our communities - rather than wrapping a lot of someone else's plutonium in our iron and dropping it to the bottom of the Marianas Trench.

Not that struggles between nations are a good thing, even so.

Standing tall is highly overrated. Diplomacy is much preferable.

Let's sideline a couple of those billions and spend them on aid, making us more popular in Indonesia, which by 2050 is going to be the world's fourth largest power, just behind India.

If we want great and powerful friends, we should at least pay attention to who's getting more powerful and who's marking time.

The real argument against this military spending, though, is that we already have an existential threat on the horizon, and it's not going to wait 75 years, or even 20.

We have global warming.

The current charade is simply a distraction - as if we'd pulled our troops out of Kokoda in 1942, say, and sent them to Western Australia to fight in the Great Emu War.

From the purely military perspective, if we do nothing we'll be faced with tens of millions of refugees fleeing famine and flood caused by climate change, and getting in the way of our Navy.

Or we could spend that submarine money productively - reskilling coal miners, installing car battery chargers nationwide, cutting down on cow farts, buying electric combine harvesters, supporting country communities beside dry riverbeds, saving the reef.

We could build Australia's soft power by supporting our universities and our artists.

I remember when we celebrated spending money on the arts when Paul Keating launched Creative Nation - it was an arts renaissance.

Even a billion-dollar community grants scheme for marginal rural electorates (to be allocated by Bridget McKenzie and Daryl Maguire) would be marginally preferable to subsidising American shipyards.

The last time an Australian submarine made a substantial difference to world history was in 1915, at Gallipoli.

The first day's landings had gone badly and the generals were contemplating pulling out, when the news came in that Submarine AE2 had pierced the minefields and got through the Narrows.

Encouraged, the commander decided that "there is nothing for it but to dig yourselves right in and stick it out."

AE2 was sunk by a Turkish gunboat four days later, but the wrong decision had been taken and the damage had been done.

How many heroic failures does Australia really need? All of our communities deserve better.