America's exceptionalism. The stiff upper lip of the British. The unruffled French "sangfroid". And the kiasu Singaporean, forever battling competition.

Are these evocative terms just lazy stereotypes, convenient shorthand for an intangible quality? Or do they express something more real? Something that summarises a community's spirit and its distinct national character?

However you might see it, there is little doubt that today the way many major Western democracies have always seen themselves and are seen by others is being tested like never before.

In one important sense, last month's US election was a referendum on Americanness, or the "idea of America". Today, Austria has its own tryst, with a momentous choice in an election for a ceremonial president. Voters appear evenly poised between Mr Alexander Van der Bellen, an independent candidate, and Mr Norbert Hofer, a far-right leader, who take opposing sides on issues such as immigration and membership of the European Union.

Across the Adriatic Sea, the Italians are on the cusp of a similar choice in a referendum. They might back centrist Prime Minister Matteo Renzi or reject his proposals to reform the legislature, paving the way for an anti-establishment movement to come to power. Next year, France, Germany and the Netherlands hold their national elections in which maverick right-wing leaders are seeking to defeat traditional politicians.

The first indication of the turning tide came with the British vote to exit the European Union in June. It sent shockwaves throughout the world. But it is with the election of Mr Donald Trump in the United States, with a large white majority vote, that the so-called "nationalistic" wave has crested.

Unlike Europe, which has long had a troubled record of integrating immigrants from other cultures, America has always welcomed them. It was founded by immigrants and its national icon is the Statue of Liberty who stood ready to welcome the successive waves of newcomers disembarking at Ellis Island. Besides, its founding documents clearly saw the new country as a beacon of hope for future immigrants.

First US President George Washington, in a letter to his successor John Adams, emphasised that immigrants should be absorbed into American life so that, "by an intermixture with our people, they, or their descendants, get assimilated to our customs, measures, laws: in a word, soon become one people".

Alexander Hamilton, one of America's founding fathers, wrote in 1802: "The safety of a republic depends essentially on the energy of a common national sentiment; on a uniformity of principles and habits…"

It is a formula that has worked. After all, the world owes much to America's inventive genius in virtually every field. However, the national character is now being tested by unprecedented changes in demography over the last few decades, driven by illegal immigrants flowing across the southern border, seeking livelihood and fleeing bloody drug wars. In 1986, President Ronald Reagan 's conservative government legalised three million Latino immigrants.

Today, there are 12 million more undocumented immigrants. They live in the shadows but still avail themselves of emergency health care and other social benefits at the expense of the taxpayer. The hundreds of thousands who get deported simply re-enter the country across the porous border. Thousands more who get arrested on serious charges are freed into the community after serving their sentences when their own countries refuse to take them back.

This comes at a time when the white Anglo-Saxon core of the country is fast changing. In 2014, it was reported that more whites were dying than were being born. In 2011, for the first time, more minority babies - Hispanics, Blacks, Asians - than white were born in America. In public schools across the country there are more non-white students than white, slightly over 50 per cent, a change that was first documented in 2014.

The white population, which was 85 per cent in 1965, is down to 62 per cent now. Three decades hence, whites will make up less than 50 per cent of Americans.

The Latinos are the largest immigrant group in nearly every American state today, replacing Germans who were the dominant immigrant group 100 years ago.

However, surveys have shown that Latinos do not integrate easily into the mainstream, in many cases even refusing to learn English. Conservatives worry that these newcomers will not integrate as well as preceding waves of immigrants, changing America more than being changed by it.

The demographic changes have been accompanied by sweeping social and cultural changes caused by the Obama administration's progressive policies. Among these: the legalisation of marijuana in several states and a host of rights granted to the gay community, including the right to marry. Gays and transgenders can now also openly serve in the military. Women have been allowed to serve in the Special Forces.

These policies have been deeply unsettling to the average white voter, who has traditionally been right of the political centre.

Taken together, these demographic and cultural shocks have served to sharpen the divide between the progressive and conservative ideologies. While the Democrats viewed America as a large diverse mosaic with islands of distinct immigrant culture fusing into a whole, the conservatives held to the need for other cultures to integrate into the mainstream.

Both parties made a new pitch to this changing America. Democrat candidate Hillary Clinton, under her campaign slogan "Stronger Together", made a bid for Latinos and other minorities. Critics said she ignored the mainstream altogether. Republican Donald Trump promised to "Make America Great Again". Detractors read a racist nostalgia into his slogan. Between the two, the voters picked Mr Trump, with the white majority voting for him in great numbers.

It is this statistic that has given observers the greatest pause. Looming over it is the inevitable question: Was this a racist vote - what a black commentator on TV despairingly and disparagingly called a "whitelash"?

Personally, I would not rush to judge. As The Straits Times US correspondent, I saw the huge crowds of enthusiastic white supporters who thronged Mr Obama's rallies in 2008. He could not have won without their support. And certainly could not have been re-elected without it.

Only time will tell if the white voter's faith in Trump will be vindicated, but to me the larger question is whether Trump can keep his promise of making America great again without changing its character.