My previous key speech in London, in October 2015, was to call for rational border protection policy. This time it was to call for rational energy policy and, judging by the reaction, people were listening even if they’re not yet ready to agree! Of course, climate does change; we all know that. What else but climate change were the ice ages, the medieval warming period when crops grew in Greenland, and the mini-ice age when the Thames regularly froze? No one denies that climate change is real. The question is how much of it is caused by humans and what, therefore, should be done about it.

This was the issue that I’d been invited to discuss by Lord Nigel Lawson’s Global Warming Policy Foundation. Lawson has remained an influential figure since ceasing to preside over Britain’s economic policy at the end of the Thatcher era. He was one of the early advocates of Brexit; and has been a consistent critic of climate alarmism. Perhaps disaster really is just around the corner; but when the past century’s carbon dioxide increase from 0.03 to 0.04 per cent of the atmosphere has made such slight difference, we should be cautious about radical policy change to cope with it. That, in any event, was the theme of my talk to about 200 people at the Institution of Mechanical Engineers, a stone’s throw from the Palace of Westminster. Among the MPs present was Trixie Gardner, Baroness Gardner of Parkes, the only Australian woman so far to sit in the House of Lords which she’s now graced for 36 years. The last time she saw me, I was in a pram!

Like Australia, in order to cope with climate change, Britain now obtains about 10 per cent of its power from wind. Unlike Australia, Britain is connected to the European power grid so can access French nuclear power and other reliable sources during calms and storms. This is the issue: how far are we prepared to impose costs and compromise reliability in order to reduce emissions? My conclusion: that we should get as much emissions reduction as we can without raising the price of power. To that end, there should be, first, no more subsidies for unreliable power (they’re not needed anyway if it’s as economic as its boosters say); second, a new government-built coal-fired, base-load power station to overcome political risk and reduce profiteering; third, an end to gas bans (with a better deal for landholders); and fourth, an end to the nuclear phobia (because this is the only way a dry country can have emissions-free base load power). ‘Primitive people once killed goats to appease the volcano gods’, I said. ‘We’re more sophisticated now but are still sacrificing our industries and our living standards to the climate gods to little more effect’. The usual suspects were infuriated. Ed Miliband, tweeted: ‘I know Donald Trump has lowered the bar for idiocy but…’ On cue, local Laborite Tanya Plibersek said it was ‘loopy’. On the other hand, Terry McCrann described the speech as ‘a seminal event’. I blush! Meanwhile, around the Westminster traps, there were only two topics of conversation: Brexit and the future of the Prime Minister.

While everyone agrees that Brexit will happen, there’s still much argument about what sort of Brexit it should be. Some want Britain to remain in the customs union but that would require the EU’s consent and would prevent any separate British trade deals. Britain would remain bound by European rules but would have no say in making them. It’s the Brexit you have when you don’t really accept the people’s instruction to leave. To these ‘remoaners’, any good (such as Britain’s current record low unemployment and record inward investment) happens ‘despite Brexit’.

To a business and politics breakfast under the auspices of the Institute for Free Trade (whose honorary advisory board I have joined), I was happy to point out that Australia does $70 billion worth of trade with Europe every year without the EU; that we managed to maintain one of the world’s highest standards of living without being in any trade bloc; and that my government finalised free trade deals that eluded us for a decade by setting a deadline and not allowing the best to be the enemy of the good. Few people are principled enough to do themselves out of a job but the Institute’s moving spirit, Dan Hannan, an MEP for Brexit, has done just that.

Among leading Brexiteers, there was much praise for our High Commissioner, Alexander Downer, for his public advice to ‘cheer up’. There certainly is a clear way forward if Britons have the courage to take it. Britain already has zero tariffs and quotas on trade with Europe and full mutual recognition of standards and credentials so why not just unilaterally maintain them?

In the wake of an unnecessary early election and a campaign that was run more like a coronation than a contest, the British government seems daunted by the challenge ahead. After a fine start, Theresa May seems undecided whether Brexit should be ‘soft’ or ‘clean’. The papers are full of unnamed cabinet ministers briefing against each other. In London everyone gets on with life and much is achieved despite a sense of drift at Westminster. In the end, the question is not so much ‘who’ but ‘what’; hence the hope May regains her mojo.

The minister who most exudes confidence is Boris Johnson. If you’re required to fight for something, it helps to believe in it! While others are diffident, all his speeches celebrate Britain’s economic, scientific, cultural and military strength. He’s also the most effective critic of the born-again socialists running Labour. As here, the next Labour government would be the most left-wing in the country’s history – so winning really does matter.