Right about now, somewhere in the United States, a rich businessman is preparing to make the billion-dollar gamble of his lifetime.

He is none other than Mr Michael Bloomberg, the media mogul turned mayor who has given himself till early March to decide if he should join the long and crowded race to the White House.

Like many others, he has grown weary of the banality of what passes as political debate among the current crop of presidential candidates. Add to that the troubling prospect - still implausible though less impossible - of a President Donald Trump.

Sharing his consternation, The Economist wrote recently: "Mr Trump has a plan to 'make America great again', a Reaganite phrase he has purloined. He wants to deport 11 million illegal immigrants and their offspring, impose a 45 per cent tariff on Chinese imports, kill the relatives of terrorist suspects and bar Muslims from entering America.

"To stanch the influx of 'rapists', he would build a 'beautiful wall' along the southern border... The notion of Mr Trump, who is backed by around 35 per cent of Republican voters, as a presidential nominee is alarming."

Pointing to Senator Bernie Sanders, it added: "There is a consolation for the Republicans. The Democrats could nominate someone even less electable."

The populist nonsense - what else do you call it? - being spouted that so endears these candidates to party activists stems in part from the deep polarisation in US politics. Indeed, President Barack Obama recently lamented that the "rancour and suspicion between the parties has gotten worse instead of better" over the last eight years.

The US, he argued, would not be able to address the challenges it faces unless it fixes the system to deliver "better politics".

"The future we want - all of us want - opportunity and security for our families, a rising standard of living, a sustainable, peaceful planet for our kids - all that is within our reach," he told Congress in his final State of the Union address last month.

"But it will only happen if we work together. It will only happen if we can have rational, constructive debates. It will only happen if we fix our politics.

"A better politics doesn't mean we have to agree on everything... Our Founders distributed power between states and branches of government, and expected us to argue, just as they did, fiercely, over the size and shape of government, over commerce and foreign relations, over the meaning of liberty and the imperatives of security.

"But democracy does require basic bonds of trust between its citizens. It doesn't work if we think the people who disagree with us are all motivated by malice. It doesn't work if we think that our political opponents are unpatriotic or trying to weaken America.

"Democracy grinds to a halt without a willingness to compromise, or when even basic facts are contested, or when we listen only to those who agree with us. Our public life withers when only the most extreme voices get all the attention.

"And most of all, democracy breaks down when the average person feels their voice doesn't matter; that the system is rigged in favour of the rich or the powerful or some special interest."

I cite this at length not out of any desire to knock the US, but because President Obama's stirring words are relevant to our ongoing discussion about just how Singapore is to achieve "good politics".

Prime Minister Lee Hsien Loong raised this in a recent speech, which was one of the best expositions on the way politics should work that I have heard in a long time.

"The business of Government," Mr Lee said, "is to govern."

Voters elect leaders to "develop policies, to implement them, to make things happen. They want policies which respond to people's needs... they want to see policies that will enable our people to achieve their aspirations, for themselves and for their children".

Good politics, he went on, must deliver government that is accountable, honest, competent, non-corrupt and effective. To achieve this, the political system has to be open and contestable, with free and fair elections, in which just about anyone could stand, not just billionaires or those with rich backers. Such contestability and accountability would keep the government on its toes.

Parliament should be the place where the big issues of the day are thrashed out openly, and decided. "You can agree or disagree, and vigorously, and you ought to disagree if you have strong views. But you must take it seriously. It is not a place where you throw chairs or swing handbags or pour water on one another; or a place where you exchange clever put-downs, but really avoid the serious issues concerning the government and the future of the country."

The political system should uphold a multiracial society, with parties having to forge "broad-based, multiracial consensus, and pursue moderate policies in the interests of all Singaporeans, regardless of race, language or religion".

There was also a need for "stabilisers", he said. While the Government should be responsive, safeguards were needed to prevent the country being "swept off course by a transient public mood, or an erratic government, which can happen".

Just how best to achieve this is worth pondering, given the critical importance of getting our politics right. A Constitutional Commission, chaired by Chief Justice Sundaresh Menon, has also invited views from the public.

Much of the debate so far has focused on the proposal to raise the number of Non-Constituency MPs from nine to 12. Some view this as benefiting the ruling party since it gives voters a chance to keep it in power while also getting alternative voices into the House. Others argue that it is the opposition that stands to gain as more of its candidates will have not one but two shots at a seat in Parliament. Once in, they could use the platform to build their reputations for the next round.

As I see it, whether having more NCMPs and giving them more powers proves to be a boon or a bane depends on how well we succeed in getting the underlying political culture here right. This is vital, if the inevitable rise in political contestation is not to lead to deeper polarisation.

President Obama put it eloquently. Singapore, too, will need to have vigorous debates on many big issues and make some hard choices. Yet, it will have to do so while maintaining the bonds of trust, and willingness to compromise, among its citizens. All sides in these discussions should accept that disagreements, however intense, need not lead to malice and hostility.

In a debate, we might all have our opinions, but we are not entitled to our own facts. Nor should the loudest and most extreme voices get the most attention, online or off, drowning out more moderate but no less sensible or passionate views.

For this to happen, voters must make clear to political players on all sides the kind of politics they want. They need to send a clear signal that all parties must uphold the fundamental principles that make Singapore what it is, such as multiracialism and equality under the law. Nor will they tolerate dishonesty or disingenuity. Politicians should be under no doubt that voters will not be swayed by grandstanding or grandiloquence. Rather, they will back leaders who stay focused on governing and making things happen.

As for the Elected Presidency, my sense is that the commission has an unenviable task. It has to relook the criteria on who qualifies to stand for election in the hope of ensuring a crop of candidates who are up to the job. Yet, narrowing the field might lead to fewer candidates, not necessarily better ones.

The commission also has to consider provisions to facilitate the election of minority candidates. Doing so, however, risks minority candidates being viewed as second best options, leaving them and their communities feeling diminished.

Far better, I think, for the commission to address the fundamental flaw in the Elected Presidency - namely the idea that an election to the post can be held without politicising it, and thereby turning an institution that should unite into a potentially divisive one.

Sooner or later, a president with his own electoral mandate will inevitably emerge as an alternative source of power, at odds with an elected government. No amount of tinkering with the selection criteria or process will address this.

There was wisdom in the previous system in which Parliament was given the task of selecting a widely respected citizen, drawn from the various racial groups, who could stand up to public scrutiny as a worthy symbol of the nation and custodian of its reserves and key appointments, to be the president.

Together with his council of advisers, the president would exercise the specific and limited powers vested in him by the Constitution, with an eye always on upholding the national interest.

Prior to 2011, there was hardly any public unease over the fact that presidents in office exercised these powers without elections or when these were not contested. Besides, many countries have independent central bankers or appointed upper chambers, where respected members of society serve as "stabilisers", trusted to do their duty of upholding the public good, outside the political fray.

In my view, reverting to that system, which worked well, should not be unthinkable.

Trump for US President? The incumbent, President Obama, has declared it won't happen, as the American people are too sensible to let it. He's right in this regard: ultimately, achieving "good politics" will depend on the good sense of voters, and the political culture and traits they insist on in those whom they chose to serve them.