Donald Trump’s decision to announce the withdrawal of American troops in the Kurdish region of northern Syria – and endorse a Turkish invasion of the region – has caught much of the world by surprise.

On top of the horrendous humanitarian disaster that this is likely to create, Trump’s decision raises broader questions about Australia’s strategic interests. Australia has, by a combination of necessity and cowardice, fought alongside Americans in every major US military action of the past century, including in both world wars, Korea, Vietnam, Somalia, Iraq and Afghanistan.

Trump’s decision is a move so bold, and so contrary to America’s post–September 11 policy, that key Republican Party allies have quickly criticised the president. Senate majority leader Mitch McConnell said that “American interests are best served by American leadership, not by retreat or withdrawal.”

Senator Lindsey Graham, a foreign-policy-hawk-come-Trump-ally who was last week defending the president’s move to involve Australia in his conspiracy theory about foreign involvement in elections, was even more damning. “This decision to abandon our Kurdish allies and turn Syria over to Russia, Iran, & Turkey will put every radical Islamist on steroids. Shot in the arm to the bad guys. Devastating for the good guys.”

Unless Trump changes his mind again, the world will simply have to deal with the terrible consequences of his whims. Those consequences are likely to include unchecked bloodletting against Kurdish forces, civilians and regional refugees.

The area in question includes a camp of refugees that is home to more than 70,000 people, including 20 Australian women and 46 children. Today The New Daily confirmed that one of the camp’s residents, 25-year-old dual Australian–Turkish citizen Zehra Duman, has been officially notified that the Morrison government has cancelled her citizenship. Her two children may now be stateless.

With an impetuous, inconsistent and increasingly incoherent president calling the shots, it may just be the right time for Australia to reconsider to what end we tether ourselves to America’s foreign policy.

This morning on Sky News Australia, former foreign minister Bob Carr added a dose of realism to the situation. “There’s a heady romanticism about the alliance … This move is a cold-blooded reminder that America will act in its own interest,” he said.

Of course, our foreign-policy concerns extend well beyond the Middle East, with the question of how to balance our strategic alliance with the United States alongside our economic relationship with our largest trading partner, China.

In the final days of the Russian monarchy, the joke around Saint Petersburg went that the two most powerful people in the empire were the Tsar and whoever had spoken to him last. This maxim has often been applied to President Trump, and given that the press release advising of his decision came shortly after a phone call with Turkey’s president Erdoğan, it’s no longer a laughing matter.

Given the events of the past week, it is surely time for Australia to have a fresh discussion about whether we want to be a part of that punchline, or start a serious conversation about formulating a more independent foreign policy.