Europe is exposed. It relies on Russia for at least 4.5 million barrels of oil each day,or about a third of its imports,and will not join the immediate US embargo. It cannot switch off Russian gas,which makes up 45 per cent of EU imports,so it talks instead of phasing out its dependence over time.

How much time? The EU has a set a deadline of 2030 to wean itself off Russian fossil fuels. It is in a race to reduce Putin’s power at the pipeline. The EU believes it can cut its demand for Russian gas by two-thirds before the end of this year,but its plan needs more than a shift to renewables. It also needs other gas suppliers.

This,in theory,could be Australia’s greatest contribution to the war. Gas shortages give Putin leverage over Europe. Gas supplies from Australia can reduce that leverage. This is why cabinet ministers have asked for estimates of how much gas Australia could produce to help. The Australian gas would not need to go to Europe because shipping more gas to Asia would allow other suppliers – Qatar,the US – to meet some of the European needs. The cost of shipping helps decide where the gas goes.

High gas prices would bring a reward,although this would be offset by the global economic shock from rising oil prices. Ultimately,however,the decision turns on a moral question. What is the best way for Australia to weaken Putin? The answer will sit uneasily with many people who believe in the need to reduce carbon emissions and therefore phase out gas.

There is no doubt that more gas is good for Europe,right now,when it confronts Russian war crimes. So what takes priority? Fighting climate change or fighting Putin?

The constraints are practical. Australia is already producing gas at close to full capacity. For all the talk of an Australian rescue in headlines last month,there are few ways to boost production of liquefied natural gas (LNG). Australia sent only seven LNG tankers to the spot market in December,according to government estimates. There is no new LNG train – the facility that freezes the gas for shipping – on the near horizon.

The Beetaloo basin in the Northern Territory,fiercely opposed by the Greens,might produce gas for export from Darwin’s LNG facility within three to five years but there is no earlier boost to supply in prospect. Santos has approved its Barossa gas field,which is off the cost of the NT,but the first gas will not flow until 2025. Woodside has approved its Scarborough field,north-west of Exmouth,but the first gas is due in 2026.

Scott Morrison and some of his cabinet ministers are looking at options to put more gas into the market without hurting domestic supplies. The options are described as limited but possible. They include “load swaps” where Australia fills an order so another producer in the northern hemisphere can ship gas to Europe.

The EU plan explicitly says it will need alternative suppliers. While the market will find more gas if the price is right,the government – whether it is led by the Coalition or Labor – will need to consider what Australia can do.

Australia has sent humanitarian aid to Ukraine and paid for weapons and military equipment to be sent across the border from NATO members. The combined effect of global sanctions and Ukrainian resistance might bring the war to an end,but a long and awful struggle is more likely. The most powerful weapon Australia can send will be a tanker full of gas.

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