Freudenberg's language was elegant and forceful, but was not, in his opinion, the reason the speech was admired later on. His words lasted because the possibility they raised - that America would be humiliated - came about. Labor had stood against the tide, at a crucial moment in history, and was - as Freudenberg had predicted - eventually vindicated.

I do not know what Freudenberg thought about Australia's current approach to America, but I can tell you what he thought of Donald Trump. Trump, he said, was "authentic, but I see the deadly side. The authentic Trump is someone who despises democracy, despises his own cabinet, despises practically everything. And is serious about the things he despises."

This week senior officials from Trump's administration will travel to Australia, where they will meet Scott Morrison. In September, the Prime Minister will visit Trump. Morrison was asked recently what he admired about the President. "He's a strong leader, who says what he's going to do and then goes and does it. I mean, I can always rely on President Trump to follow through on what he says."

A few days after that, the President said something, and it was explosive. He tweeted that several US senators should go back to "the totally broken and crime-infested places" they came from. The four senators he was talking about were all women of colour.

This is incredible, appalling behaviour from an American president two decades into the twenty-first century - a deliberate incitement of racial hatred. And it does - or should - raise questions for our government. What should its response be? Should our Prime Minister be meeting with this man? Will Morrison praise Trump again?

I know that for many people who work in politics, or around politics, this will seem absurd. The American alliance is foundational. Even to ask such questions is taken as a sign of radical crackpottery. And so, if you are one of those people, ask yourself this instead: at what point will you think it is OK to ask those questions?

Morrison has given his opinion on Trump before. In a speech in 2017, he urged his colleagues to communicate "with authenticity". What did he mean by that? He named two models. One was British Labour leader Jeremy Corbyn. The other was Trump. Both, he said, had taken "on the role of the authentic outsider; challenging a system that many voters did not think was serving them any longer".

Interestingly, those comments closely mirror Freudenberg's description of Trump. I doubt Morrison despises democracy, but he certainly has been willing to express a strongly sceptical view of the worth of various democratic institutions. Repeatedly, since becoming Prime Minister, he has poured scorn on the system he is part of - or perhaps, he would say, merely challenged it.

Just last week he made clear what he thought of the grand tradition of Liberal MPs speaking out on policy. Shut it, he told them. The independent public service got a talking-to as well: it should "get on board and implement the government's agenda". Neither of those directions is entirely unfair. But they do betray a certain attitude: Don't stand in my way, this is my government now.

He also said he would respect the capability of public servants. But actions are telling: last year, senior public servants were not consulted about the misjudged relocation of Australia's embassy in Israel. He has also said, "I expect the ABC board to do better. And if they don't, well they can expect a bit more attention from me." That's the independent national broadcaster. He won't be funding "global climate conferences and all that sort of nonsense". So much for international governance.

A debate, of sorts, has recently sprung up in some quarters: is Scott Morrison exactly like Donald Trump? It's a distraction. He's not, but so what? The crucial fact is that a certain set of political tactics is becoming normalised, and Australia is a part of that. Contempt for democratic institutions is seen as a useful attitude for a politician to have. Explicit racism as a political tool is no big deal. A leader leads, and everyone else better do as they're told.

In hindsight, Calwell was right. But at the time he risked ridicule in questioning what seemed reasonable. The truth is that many people sense, right now, that something strange is looming. But isn't something strange happening already? Aren't these changes worrying enough on their own, whatever happens next?

Not every significant historical moment is as conspicuous as entering into a war. My guess is that most historical moments are as conspicuous as we allow them to be.