Former Prime Minister Malcolm Turnbull has warned the world faces dangerous and uncertain times over the next four years with the very real possibility of President Trump Mark II.

Speaking at a renewable energy summit in Sydney on Thursday, Mr Turnbull said a Trump presidency would lead to geopolitical instability, rattling the world’s progress to net zero and global clean energy leadership.

It would also throw into doubt the US Inflation Reduction Act, which was  passed by Joe Biden in 2022  and contains major spending on programs to accelerate the US’s transition to net zero.

Mr Trump appears to have the Republican presidential nomination in the bag after a string of statewide victories on Super Tuesday, and has repeated his intention to ‘drill baby drill’ if re-elected in November.

“Geopolitically it’s a scary place out there,” Mr Turnbull said on Thursday.

“America will cease being a clean energy advocate just like it did during (Donald Trump’s) first presidency, so it will be up to other countries to take up that leadership.

“This is a guy, whose slogan is ‘drill baby drill’, who thinks global warming is a hoax. So I think it will be a real battle and a major setback.”

A less reliable America

Mr Turnbull also said Mr Tump had previously demonstrated a ‘disturbing’ fascination with dictators like Russia’s President Putin.

“A Trump-led America will be a much less reliable America,” Mr Turnbull said.

“He’s erratic, he’s unpredictable, he’s capricious. We’ve seen this film before. It will be a much more uncertain environment and the question is will it encourage adversaries to take their chances, whether it’s China and Taiwan, Putin would absolutely welcome a Trump victory.”

Mr Turnbull said the Republican Party has been captured by Mr Trump, who now dominates the party in a way he didn’t in 2016, and his base.

“The  MAGA movement has basically taken over the republican party,” he said.

“Its no longer a traditional centre right pro-business party, you’ve now got  a  populist, and in some respects very radical party, that’s motivated by issues that are not really economic but about values and ideology.”

Implications for Australia

Mr Turnbull said one of the biggest challenges for  Australia is that it has become more dependent than ever on the US, at the very time where the US is becoming less dependable.

“The more logical approach is Australia should be seeking to be more self reliant,” he said.

“Global leadership is going to be very very challenged in the next four years I’m afraid and it’s very hard to predict where it’s going to land.

“It will be a wild ride.”