Kim Beazley arrived in Washington, DC, in the middle of the snowiest winter in the capital since 1880, in February, 2010, a year after Barack Obama was sworn into office.

Seeing a visitor to the front gate of the rather grand residence Australian ambassadors enjoy in the US capital, Beazley slipped on black ice at the foot of the long sweeping driveway, injuring one knee as he fell, the other as he hauled himself up.

He needed keyhole surgery to both and had to defer his appointment to present his credentials to the President in the Oval Office.

This week as he gave up the post to Joe Hockey, Beazley's voice was hoarse. Some time after he had finished a hectic round of farewell functions but before he received Prime Minister Malcolm Turnbull, in town for bilateral talks with President Barack Obama, Beazley had managed to pick up a bug.

On Tuesday night during a reception at the residence he stood at the top of a small flight of stairs overlooking the crowded drawing room and made a brief address.

The PM was off to another dinner and Beazley was to escort him and return, but be didn't want the party to break up in his absence he explained.

"Hang about," he croaked to his guests.

Turnbull interrupted. "He's just trying to empty the cellar before the Hockeys arrives," he said before the two men headed down the corridor.

Beazley spent a crucial six years as ambassador, including the most significant years of the Obama era. He helped develop deeper military ties as the wars in Iraq and Afghanistan were first quieted, then slowly transformed into a war on terrorism. He was there to explain to his hosts when Australia abruptly changed its prime minister, five times.

He became a significant voice in the American capital when the President announced a "rebalance" to Asia and the Pacific, and he has been a force in lobbying for the Trans Pacific Partnership, the trade agreement that might one day lend that policy much of its substance.

It is telling that when the Abbott government took power in Australia and it went about a purge of Labor appointees, Beazley's term in DC was extended.

He became the most popular ambassador on the Hill, according to one observer.

When Beazley arrived the US was in deep recession and endless talk about the great American decline was matched only by discussions of China's inexorable rise. Today the US economy is the envy – perhaps the hope – of the western hemisphere.

Nonetheless the nation remains bitterly divided, its Congress more effective at blocking reform than basic governance, and its presidential politics has been swept by sometimes ugly nativist populism.

Days before he left Beazley sat down with Fairfax Media  to talk about how the US fared over the Obama era, and why the sometimes ugly political environment has not abated in the face of economic recovery.

"In my normal working week I would be in the State Department and the NSC [National Security Council] half a dozen times and in the Pentagon once a fortnight and the intelligence services once a fortnight," says Beazley.

He also travelled widely, and, he says, watches a lot of early morning TV, swapping back and forth between the morning news and political programs.

"I'm always looking at the rallies. I want to see the faces behind the politicians. I'm always interested to see the Trump rallies.

"Not many women and not many people of colour in the environment behind [Republican candidate Donald] Trump. But they do look to me, very much, the folk who are there, like the folk I'd see at the average Labor party branch meeting."

These were the Americans who were angry even before Beazley arrived. They joined the Tea Party, they loved Sarah Palin, they resent the federal government, and many are certain that Obama is working against their interests.

Beazley believes that their anger is legitimate even if misplaced.

"Attitudes always emanate from a practical underpinning," he says.

"The attitudes that we've just been talking about in relation to the American middle class, is because in reality they are suffering. It is very hard to make ends meet without three or four jobs in the family. It's hard to be able to afford your house, even though things are cheaper here, much cheaper than in Australia. It's hard to afford college now."

By Beazley's analysis America's middle class is in revolt because it has been battered for over a generation, and at no point has the federal government stepped in to its aid.

The multinational business was refined, with head offices kept on shore and manufacturing deported, labor laws crippled unions and automation whittled away even more jobs. Free trade agreements accelerated the process.

"In the space of a decade and a half the future of the American middle class was destroyed. That's quite dramatic."

Beazley agrees that this happened in other western nations, but never to the same extent, and not without the federal government stepping in to help.

"The fact then that there was no government program, nothing connecting with the federal government, basically, that was the germination, if you like, of the attitudes that now exist. There is no contemporary member of the white middle class who has experienced an era of positive reflection on government. None. They're all dead now.

Those who experienced that era are dead.

"In Australia, we never confronted it with the intensity the Americans confronted it. But, crikey, when we did, massive tax cuts for the middle class, the extension of tertiary education, wholesale, universal health care. The Australian government went wacking in with a massive middle class program that was the exact opposite to what happened here."

The generation buffeted by these changes, he says, has no positive ties left to the federal government. Education is managed by the states, healthcare is largely provided by employers.

Then there are the short-term causes. The growing ideological division in America started in the 1980s when Ronald Reagan was able to forge a coalition between Evangelicals and the so-called Reagan Democrats.

The culture wars since have divided America further.

Since he arrived – since Obama was elected on a promise of hope and change – Beazley believes the division has only increased. Mistrust in government has increased.

But by objective measures the American outlook is far better than it was.

When Obama was elected the economy was shedding 700,000 jobs a month.

Since then, in no small part due to Obama administration stimulus measures, economic growth is modest but stable. Over 14 million new private sector jobs have been created, setting a record 70 straight months of jobs growth.

Meanwhile Obama's domestic agenda – particularly Obamacare, moves to reduce student debt and boost the minimum wage - have been designed specifically to ameliorate the problems that Beazley identified.

Why has this not eased the mistrust?

"Maybe those policies will have an impact on people's attitudes a decade from now. Maybe not. But they have no chance to change that now," says Beazley.

Obama himself has at times shown his frustration at this. "Anyone claiming that America's economy is in decline is peddling fiction," he said during his State of the Union address last month,

"Now, what is true -- and the reason that a lot of Americans feel anxious -- is that the economy has been changing in profound ways, changes that started long before the Great Recession hit; changes that have not let up."

The mistrust and division have had profound consequences for America and significant ones for its friends too, Beazley concedes.

The forced across-the-board spending cuts known as the "sequester" – a Frankenstein consequence of ugly budget negotiations – have hurt America's defence planning and spending, he says.

Beazley gets animated when he lists the next generation weapons systems that could play a role in maintaining security in our region that have been delayed by sequesters. He speaks of B3 bombers and ship-borne lasers, very fast missiles and underwater robots.

"Political logjams affect the deployment of these systems yes, they affect the ability, too, for a rational calculation to be made on priorities, and these are not decisive and destructive, but they are annoying, and they do feature in the [diplomatic] conversation."

Similarly, Obama's Middle East strategy has left some Americans, accustomed to superpower status, disquieted.

American leaders he notes, face problems that those of other nations do not, simply because it is the one nation capable of expressing force around the world.

"The United States could rub out ISIL in three  months but what sort of politics would you have left in the Middle East?" says Beazley.

But despite criticism from the right, Obama has chosen not to.

"How do you get out of there? What have you found yourself in the middle of? There is a sort of comprehension here [in DC] that there is a major struggle going on in the world of Islam which has many manifestations and angles to it, in which we [the US and its allies] are not actually particularly influential ideologically. We may be influential physically, but not ideologically. So that level of engagement is not sensible and therefore it is avoided."

Beazley believes that criticism that during Obama's second term the rebalance to Asia and Pacific has been abandoned due to the demands of the Middle East was fair to a point.

But he says it denies the "underlying reality" that Obama will be the "only American president there will ever be who has lived an Asian life".

Obama, he says, has a unique understanding of the importance of Asia not only to the world, but to American – and Australian - prosperity.

"He comprehends that accessing those markets is going to be critical to American prosperity, getting more and more critical because… that great economic engine which is American domestic consumption is not as potent a weapon of economic prosperity as it once was."

America, he says, needs a new middle class, and it is in Asia.

Whether or not the next American president will agree is not yet clear, but the anger of the Obama era is playing out here too.

Beazley explains the phenomenon of Donald Trump by casting back a year to a conversation he had with a friend he will only describe as a very prominent Republican.

"This is the state of affairs," Beazley recalls saying. "The Republican party now represents the white working class, attitudinally. Be it on guns. Be it on same sex issues. Be it on migration. Be it on the religious matters. You represent the attitudes of the white American working class.

"Your problem is you don't represent their interests," referring to Republican policies that had allowed economic inequality to grow so fast.

"At some point a magic man is going to come along and he is going to run a campaign which will absolutely destabilise your model of politics and cause you to question the direction of the Republican party."

This man turned out to be Donald Trump, who though running as a Republican is campaigning as much against the party's own establishment as he is against the Democratic Party.

Beazley's view is that Trump's popularity is the product of the Republican Party's failure to develop a program for the white middle and working class it has won over from the Democratic Party.

Of course, Trump has no such plan either.

"The appeal of Trump is that somehow or other . . . out of his apparent business success, everyone will be winners. It's a magic man concept. It's not a program. He doesn't actually have a program."

Will he get found out?

"Maybe not," says Beazley. And if Trump wins the nomination, he says, there's no ruling out one horse in a two horse race, though he believes a Trump victory to be unlikely.

As Beazley leaves the relationship between the two nations is in good shape, even if some fret for the rebalance. The alliance has bipartisan support in both nations and Australia's voice is heard clearly in DC.

One observer notes that Hockey's first job will be to differentiate himself from his predecessor.

Beazley says he will miss "just about everything" of his time as ambassador. If he could change anything he would perhaps loosen purse strings in Canberra.

He believes Australia could do a better diplomatic job by "thickening" its diplomatic efforts in the countries it is represented in, and its capacity to analyse and harness all the information its diplomatic corps pumps back to Canberra.

"I don't think anyone in the department will thank me for saying that, but I am gone anyway," he says with a gruff laugh.