It is sometimes difficult to convince Australians and Americans that they are not identical, save for different accents and footy preferences. However, there are some stark reminders of how and where these two political cultures can sharply diverge.
This year's Lowy Institute Poll demonstrated that President Barack Obama is strongly favoured as President - at least by Australians, with an extraordinary 80 per cent to nine per cent lead over Republican candidate Mitt Romney. (In 2008, Obama was preferred by 73 per cent of Australians polled, against 16 per cent for Senator John McCain.)
According to the latest national polling in the US, however, President Obama is ahead of Mitt Romney by only 47.5 per cent to 44.7, a less than decisive 2.8 per cent lead at this stage, within the margin of error for such polls.
More importantly, the two countries have demonstrated a very sharp difference in their approach to organised labour and the regulation (or de-regulation) of the labour market.
Last week, Wisconsin Governor Scott Walker successfully fended off a recall vote after only 18 months in office. A conservative Republican who often says that he has consciously modelled himself on Ronald Reagan, Walker quickly moved to make industrial relations his battleground, stating that it was ''time to draw a line in the sand''.
An anti-slavery state from its foundation, Wisconsin was the first American state to enact workers compensation laws, unemployment insurance and progressive income tax scales, and in 1959 was the first to authorise collective bargaining by public sector employees.
Although it produced Senator Joseph McCarthy in the 1950s, the state has generally trended somewhat left of centre in modern American politics. For example, the Democratic candidate has won Wisconsin in every presidential election since 1988, including Obama in 2008.
Citing the need to rein in government spending, Governor Walker quickly set about dismantling union power by legislating to end closed-shop arrangements, eliminating compulsory dues collection, and stripping most public sector employees of their collective bargaining rights.
In order to gain sufficient votes among even Republican legislators, the final version of the law exempts police officers and firefighters from the controversial ban on collective bargaining. (The initial court challenges have focused on the fact that public sector workers are no longer being treated equally under the law.)
Not surprisingly, the unions representing teachers, nurses and other public servants leapt into action, in a dispute regarded as setting new political precedents with national significance. Accusing Walker of ''trying to turn Wisconsin into the Tea Party capital of America'', the unions mobilised to trigger a recall election, collecting over one million validated signatures of Wisconsin voters endorsing this course of action, which was twice the number needed.
Walker defeated Milwaukee Mayor Tom Barrett, whose nomination by the Democrats had been strongly supported by organised labour (over potentially more dynamic and charismatic candidates).
Walker's campaign was propelled by an enormous fundraising effort, led by the Koch brothers, billionaire industrialists and generous supporters of conservative causes (including the Tea Party movement), as well as the new wave of corporate Super-PACs authorised by the Supreme Court's controversial decision in Citizens United.
Two-thirds of Walker's campaign funding came from outside Wisconsin, and he ultimately outspent his Democratic challenger by a factor of somewhere between seven and 10.
The victory has propelled Walker to national prominence and provided him with a certain star quality (think of the young Peter Costello after the Dollar Sweets case), with stories already appearing about him being a potential vice-presidential pick for Mitt Romney (unlikely), or a strong candidate for the Republican nomination in 2016, if Obama is re-elected.
While Republicans would like to characterise Wisconsin as a new ''battleground state'' that is winnable for Romney, it appears that voters in the recall election clearly distinguished that race from the presidential election in November. Exit polls indicated that President Obama was preferred by a margin of 52 per cent to 43 per cent over Mitt Romney by the voters that had just delivered Scott Walker a famous victory. Asked which candidate would help the middle class, Wisconsin voters preferred Obama by an even larger margin (47 per cent to 36 per cent).
In many respects, the Wisconsin election is reminiscent of the 2007 federal elections in Australia, in which the Howard Government's WorkChoices legislation was the flashpoint.
Unions forcefully campaigned on the basis that the law had gone too far in curtailing workers' rights, upsetting the required equilibrium between security and reasonable wages and conditions for workers on the one hand, and flexibility and profits for management on the other.
In that event, the Australian Labor Party, riding on the back of a well-funded and high-profile union campaign, decisively ended 12 years of conservative Coalition rule, with John Howard not only losing government, but his own seat in Parliament. The Coalition's own post mortems clearly identified WorkChoices as the culprit, and Opposition Leader Tony Abbott is adamant that the policy is dead and buried, never to be disinterred.
David Weisbrot is professor of legal policy at the United States Studies Centre at the University of Sydney.