All nations, at all times in history, are the products of human imagination. Even those nations given shape by nature – existing inside helpfully-defined shorelines and mountain ranges – really only emerge through the myths and traditions of the people that settle in them. There is no natural reason why crossing from England into Scotland makes you suddenly aware of a certain “Scottishness” that permeates the air.

That’s not to say that the people don’t become shaped by the land. Certain physiological changes can take place in a people based on where they live; those living in high altitudes have lungs better suited to living with less oxygen; the men and women of Yorkshire have stronger legs because they climb more hills; city folk might be more affluent than those living in the country but probably more unhealthy too.

These are the deep structures that underlie our existence and, in this, landscape can certainly inform national identity which then feels rooted in reality. Yet national identity itself remains fluid and unfixed, such that there’s rarely just a single notion of what nationality entails. Regional variations exist in all countries, and within regions, there are almost as many identities as there are individuals willing to speculate about such a hazy concept. Nationalisms do emerge, of course, as a form of group identity, but they’re always competing with the more basic human urge towards individuality and it’s individual freedoms that make innovations happen and nations flourish.

When Donald Trump’s addresses a joint session of the US Congress at 9pm tonight (2am GMT), his vision of America will be strikingly different to those shared by much of his audience. Trump’s America exists largely in the minds of those who look on this President as the first, for a very long time, to pursue a properly conservative agenda. To that base, Trump has been a revelation. It’s why they routinely ignore all the media outrage caused by his tweeting and care little for the rumours that surround his private life. Even Russia, they say, is a distraction. What they care about is something that goes beyond simple politics. It’s grander, even, than momentary victories over Tax bills or travel bans. It’s a state of both mind and nation; a concept of America that they had long feared passed.

The problem for these conservatives is that the America promised by the election of Donald Trump bears little resemblance to much of real America. Even if the election result was not dramatically changed by Russian meddling, Trump still lost the popular vote and only won through a quirk of the electoral college. That’s the second time in a short period of time that a Democrat majority has been denied power by this archaic mechanism, and it’s hard to see how it will be allowed to continue should it ever happen again.

This, really, is the state of modern America: a nation experiencing a quixotic reverse in its modern trend; an increasingly Democratic country exhibiting a spasm of arch-conservatism; a demographic time-bomb ticking beneath the posteriors of a GOP who suddenly look older and even more backward looking.

Yet to Trump supporters, the momentary victory seems to offer hope for the future. Certainly, they might also be right if they’d hoped for a more polarized political atmosphere in Washington and the re-emergence of nationalist arguments in public discourse. What seems, however, like permanent a truth in the Bible Belt looks very different when viewed from New York or San Francisco. A few years of draconian immigration control will do little to stem the demographic shift that’s been happening across the south of the country. A few sops paid to the coal industry will do little to turn around the consensus of opinion (and, indeed, market forces) that suggest the future of energy lies in cleaner and cheaper means of production.

A government filled with creationists does nothing to halt the advances in the scientific method, based on evidence – meaning that climate change will remain a focus of scientific and political action over the coming decades, if not a century and beyond. Regressive polities towards certain social groups will do nothing to change the attitudes of a new generation who are more tolerant and open-minded than their parents.

Donald Trump will stand before Congress this evening and, like King Cnut, proclaim that he’s halted the tide. Yet there’s nothing about this Trump revolution that suggests that anything other than the tide will ultimately prevail.

This is also why Trump remains such a point of fascination as well as frustration. He is the unchanging beacon that marks the rocks where the steadfast and dogmatic belief in the old ways begins.

Yet the issue is not simply one that affects Trump and the Republicans. It’s much broader. In the UK, Theresa May will face a leadership challenge if she proves incapable of reconciling the two irreconcilable wings of her party. There’s little to suggest that she will be capable of doing just that but, in truth, that’s the problem with irreconcilable problems. They tend to remain irreconcilable. The immediate challenge for the UK conservatives is to reach some pragmatic muddle that will least upset those seeking a compromise with Europe (and a few that would simply scrap Brexit entirely) and those that are holding out for the hardest of Brexits. It will not be easy and it will certainly not be pretty. Labour face exactly the same problem within a party no less divided between those that might broadly be termed pragmatists and the ideologues.

What history proves, though, is that history prevails and that cultural forces are sometimes unstoppable. The world will not get larger in the coming decades. It will get smaller, with all the revolutionary and reactionary forces that will entail. Most of the solutions to our problems will come from the new world and not from the old. Some will be technological: drone technology tracking the borders instead of concrete walls built over thousands of miles; new advances in agriculture helping to make the most out of finite resources; improvements in healthcare and treatments. Others will be ideas that help us better understand our economies, markets, and how our governments respond to more automated industries that require fewer low-skilled workers. Another of these grand shaping visions will undoubtedly be the solution to Brexit; a solution that must be pragmatic, workable, and suited to our place in the modern and furiously competitive world economy.

None of it will please the reactionaries, of course, but this struggle between new ideas and the old is as ancient as knowledge itself. A solution to Brexit will be found as America will ultimately find solutions to those environmental, social, and cultural problems that remain unsolved by the Trump administration’s belief in unfettered industry. Progress is the Promethean gift that cannot be given back.

For this brief moment, the old America might look like it’s in the ascendancy, but Republicans will eventually have to win the hearts of that new America that’s always going to emerge. To do so, they will have to change, irrespective of Trump’s talk of his spectacular achievements in making America great again. It also means that this year’s State of the Union is probably going to be more of a blip than a true indicator of the future. It signals where reactionary American now sits rather than where America’s future lies.