When Scotland held its independence referendum in 2014, both sides agreed it would settle the question for a generation. But apparently a generation lasts about two and a half years. On Monday, Scottish First Minister Nicola Sturgeon announced that next week she will begin legal proceedings necessary for another referendum, to be held by 2019.

Sturgeon said that Britain’s decision to leave the European Union means that Scotland needs a new referendum. The majority of Scots voted to remain in the EU, while the United Kingdom as a whole voted to leave.

Last summer, Scottish National Party leaders gave two additional reasons for Scotland to hold a second referendum: 1) the UK Parliament’s decision to renew Britain’s nuclear deterrence and 2) if Boris Johnson became prime minister. It’s hard to escape the conclusion that after being defeated in 2014, they wanted another vote and were simply searching for a good excuse to hold one.

Despite the fact that, according to one poll, only 1 in 4 Scottish voters actually want a new referendum, it seems certain to happen. The only argument is when.

Ms. Sturgeon wants the vote to occur by spring 2019, before Britain is out of the European Union. British Prime Minister Theresa May has indicated that she will insist that the vote be held after Britain has completed the process of exiting the EU.

Under Section 30 of the Scotland Act, the Scottish Parliament will first vote on whether or not to hold a referendum. Then the UK Parliament in Westminster must approve it. Westminster could block the decision, but Ms. May seems unwilling to do so.

With the process beginning next week, Britain will be consumed by a divisive debate over the next few years. After the last vote, nearly 40 percent of Scots said they believed the referendum had “caused harmful and lasting divisions in Scottish society.”

Britain is already struggling with one uncertainty that will affect the country for generations to come: its post-Brexit relationship with the EU. Britain has voted to leave the EU, but much still remains uncertain. What will the UK’s new relationship with the EU be like? What trade agreements will Britain have with the rest of the world? With another Scottish independence referendum on the line, the UK will once again be asking, Will we continue to exist?

Since the 2014 Scottish referendum, the UK has played a diminished role in the world—focusing on its internal issues. In many ways, there’s nothing wrong with this; Britain’s role in the EU needed to be addressed. But if Ms. May gets her way—which seems likely—Britain will spend the next few years focused on Brexit, then hold another Scottish independence referendum around 2021. That’s getting close to an entire decade lost on self-absorption in existential questions.

Furthermore, if Scotland leaves, Wales and Northern Ireland have said they want their own referenda too.

I remember the rancor and division of the last referendum all too well: The shock for those of us living south of the border, finding out that many to our north passionately hate us; the uncertainty as I watched the polls and wondered if my country would soon cease to exist.

We are going to go through all of that again, reopening old wounds and gouging new ones.

The leaders of the Brexit movement portrayed the vote as the solution to all of Britain’s problems. If we would only quit the EU, we could go out into the world, unencumbered by meddling from Brussels. Prosperity would return. Britain would once again be a respected, major power.

But today’s post-Brexit world looks too familiar—the same divisions, the same arguments, the same problems.

This is not to say that the EU was good for Britain—it wasn’t. But is there clearer proof that Brexit doesn’t solve everything? Our biggest problems come from within.

Britain is still a country lacking vision and purpose. As Brad Macdonald wrote:

No one has provided a rousing, positive vision of what it would mean to remain part of Britain. No one has reminded the Scots of their illustrious history with England. No one has reminded them of what England and Scotland have accomplished together—and provided a vision of what they could accomplish together in the future. There once was a dream called Britain. Being British meant something—changing the world, righting wrongs, civilizing distant lands. But now the world is not our problem. There are no rights and wrongs—just British neo-colonialist arrogance—and sadly, a prevailing sense of shame of its history.

Where is the hope-filled vision of Scotland’s destiny should it remain united with England? There isn’t one. Why? Because England doesn’t know what it means to be English—and consequently, it doesn’t have a clear vision of its own destiny.

We are here today because the very quality—the defining sense of identity—the clear and indomitable sense of what it means to be British—that for more than 300 years has bound Scotland to England, and England to Scotland, is gone. This sense of identity had been diminished for decades, chiseled away by revisionist historians abolishing the British Empire, by multiculturalists embracing other cultures and religions, and by politically correct politics undermining patriotism and loyalty to Britain.

Really, we shouldn’t be at all surprised by what we are witnessing today in Scotland. This moment has been brewing now for decades. It’s just as King Solomon stated 3,000 years ago: “Where there is no vision, the people perish.” Today there is no vision of being British, and Britain is perishing.

Because of this, we are consumed by these arguments both before and after Brexit. It’s clearer than ever that we are a country that has lost its way. It is this lack of vision that caused the first vote. Winning that vote didn’t fix our problems—and now we’re about to hold another.

For more on what these constant divisions say about the country, read Brad Macdonald’s article “Without Scotland, There Is No Great Britain.”