The British Empire is no more. The unquestioned supremacy of Ulster Unionism is no more. The living stream of history left all that behind over half a century ago.

Two marches were held in Ireland last Saturday. In Derry, in the north, the apprentice boys marched to commemorate the shutting of the city's gates in 1688. Do the math, that's 330 years ago. They set a giant effigy of Robert Lundy, an army officer accused of treachery in the long ago, on fire.

Meanwhile in Dublin, in the south, a national demonstration was being held to demand public housing for all and an end to evictions and homelessness. That's a movement that, instead of reenacting the past, was looking to change the country's present and its future.

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So a tale of two cities then. And two tribes. And two distinctive outlooks, on the same day. But what's behind this marked northern reverence for the olden days? Is it nostalgia or a commemoration of the lessons of history, or something a bit more pointed?

Listening to Boris Johnson's speech at the Democratic Unionist Party (DUP) conference two weeks ago, Ian McCrea, the former MLA (who was wearing a Union Jack tie to the event) told the press: “The one thing about the DUP is that we don't look to the future and say: “This is where we want to be one day.” Because where we'd like to be is where we are.”

In other words, if you're on the top of the pyramid, why change or alter your views, even when you can plainly see the foundations below you are shifting? Is there any point making an appeal to you when it's obvious you have no particular interest in responding? And if “not an inch” is your only answer, is that politics or supremacy?

Hoping that those who are under your foot won't move isn't much of a plan, as fifty years of the Civil Rights movement and the Troubles showed us. But if standing firm is the only way you can stem their dissent that's what you'll do isn't it?

Progressives tend to see life as a long straight road to the future, a direct path on a journey toward “a more perfect union.” So they labor over years and decades to create broadly positive social and political change, building toward their goal of larger foundational change, and occasionally they have spectacular successes.

The marriage equality vote in the Republic in 2015 is a perfect example of this kind of forward planning. It was a genuine national course correction, another milestone on the long road to a more just society.

But conservatives on the other often view the world as a kind of smoking battlefield, one where every gain they have made is under relentless threat of attack.

That means they can never really take off their suits of armor. It means they're under relentless siege, forever on the defensive, it means they see life as a kind of endless war. It's an entirely different way of being alive in the world.

Progressives like to surf the tide of history and change, but conservatives resist those forces. They become, to paraphrase the Irish poet W.B. Yeats, stones in “the living stream” of life.

Being a big stone in the living stream of life is a terrific image of self- determination. It means the rest of life simply has to bend around you, adapt to your presence and supremacy, because you have become so powerful, so much so that you barely even notice that same “the living stream” is slowly grinding you to powder.

So streams and stones. Power being ground to powder. It's a process. It's happening right now. It's been happening forever. The only constant, no matter how imperceptible, is change. You can debate whether it's better to be a stone or surf on the stream. Philosophers have been doing so for millennia.

Conservatives maintain their power base in both Ireland and America by being far-seeing and anticipating the moves of their many opponents before they have even made them. When you are fighting to maintain your reality and protect your dominance, you have to do this. The forces ranged against you move much faster. You can't ever let your guard drop.

It does something to you, this perception of life as an endless conflict, an endless siege. It makes you insular, suspicious and watchful. It drives you inward, it slowly shapes your character and your expectations. Every gain made by your neighbor starts to seem like a surrender from you. That's a painful way to live. That's a kind of harm, isn't it?

Brexit has clearly shown us all that the DUP and the Conservative party still negotiate with the E.U. as though there was still an all-powerful British Empire who will ensure they have the last word because they always do. All their reflexes have been shaped by centuries of that unquestioned supremacy.

But the British Empire is no more. Their supremacy is no more. The living stream of history left all that behind over half a century ago. That's what makes it all so poignant. What we are witnessing now is that truth and its implications are finally beginning to dawn on them.

It's about time.

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