Three weeks after Britain voted to withdraw from the European Union, newly minted Foreign Secretary Boris Johnson was full of optimism about the UK's future as a world power.

Leaving the EU, Johnson argued, meant an opportunity to focus on “reshaping Britain’s global profile and identity as a great global player”.

It was a favourite theme of the Leave campaign: the Brexit vote was a gamble, but one that could spur Britain on to renewed greatness.

Now, after six months of inconclusive negotiations, a consensus on Britain’s role in the world is emerging - at least in Brussels - and it’s not the one Johnson envisioned.

“Obviously once the UK has left the European Union it will no longer have the same status as it had, either regards Europe or the international scene,” European Commission President Jean-Claude Juncker told Euronews earlier this month.

So is Britain really destined to become a sideshow on the world stage? And why does it matter?

Death of a global powerhouse?

If Theresa May was trying to recapture the momentum of the “red, white and blue” Brexit during her visit to Canada this week, the reaction in the Canadian press suggests she failed.

The Prime Minister’s attempts to secure a trade deal along the lines of the one Canada recently agreed with the EU came off as “desperate”, says CBC’s Evan Dyer, and exposed her “weak hand”.

Instead of opening bold new trading frontiers, Britain is visibly scrambling to hold on to the deals it already has, he writes. Brexit campaigners insisted that other countries “would be lining up to do business with the UK” after the UK triggered Article 50. “That hasn't happened.”

May’s game of catch-up with Canada was a forerunner of things to come, says Politics.co.uk editor Ian Dunt. “For those who care to look, the signs are everywhere. Brexit is dissolving Britain's status in the world.”

Brexit was conspicuous by its near-absence in Juncker’s annual ‘state of the union’ address to the European Parliament last week, which instead focussed on a new dawn for the bloc.

Andrius Kubilius, a former prime minister of Lithuania who sits on his country’s Brexit committee, was blunt in his assessment. “Several months ago getting a deal with Britain appeared to be the most important thing we needed to get done. It doesn’t feel like that any more,” he told The Guardian after Juncker’s address.

Even when other countries are paying attention to the UK, it’s often for the wrong reasons. With a stalemate in Brussels, recent Brexit coverage has been taken up with internal squabbles in Cabinet and public spats between ministers unable to agree on a vision for Brexit.

It’s an undignified portrait of the nation, says ITV political editor Robert Peston, especially given that “one of the benefits of Brexit was supposed to be to show a renewed and confident UK setting the global foreign policy agenda”.

The paltry audience who gathered to hear Theresa May address the UN on Wednesday was another sign that Britain’s voice no longer automatically commands attention on the world stage.

“Empty threats to an empty room,” was how The Independent summarised the speech, adding that the pro-Brexit media’s failure to address the elephant in the (empty) room was another example of Britain’s decades-long struggle to accept its status as a “declining country in an improving world”.

Ashes of empire

But why is Britain so obsessed with its international standing? It is, after all, perfectly possible for countries to enjoy a high standard of living and economic prosperity without playing a leading role on the world stage - we only have to look at our European neighbours like Denmark or Austria for proof.

It all comes back to Empire, says Cambridge University professor Nicholas Boyle, writing in the New European. The vote to leave the EU was, in part, motivated by a sense of British exceptionalism derived from centuries as a colonial overlord.

For the English in particular, membership of the EU represents a “terrifying truth”, he writes - “that they have to live in the world on an equal footing with other people”. Eurosceptics’ warnings about an EU “superstate” masked a far more banal fear, he argues: a future where Britain would be “just another member of a team”.

A new Britain

So what does the future hold for post-Brexit Britain? Foreign policy will not change overnight, says David McCourt, a sociologist at the University of California.

A probable scenario is that Britain remains an “active international player”, but with a dimished international profile comparable to that of Australia or Canada, while France and Germany take a more prominent leadership role.

Over time, McCourt says, Britain “will be expected to play the role of regional power, rather than great power with a residual extra-regional posture”.

The global indifference shown towards Britain in recent weeks is a painful illustration of this increasing irrelevance, says The Independent, but it is a lesson that the country needs to learn in order to move forward and accept its reduced sphere of influence. Without meaning to, “it’s possible Theresa May has finally helped us find our place”.

Not so, Ian Dunt argues, this time writing in Prospect. Left-wingers who continue to cast Brexit as the latest indignity in a slide towards impotence and insularity that began with the dissolution of the empire are mistaken.

That narrative overlooks the reality that Britain has been growing steadily more prosperous, more outward-looking and more influential since joining the EU as the “sick man of Europe”, Dunt argues.

“Brexit was not a rejection of British decline, but of British success,” he says. It was a multicultural, forward-thinking, globalised Britain that was “cut off at the knees by misty-eyes imperial fantasists” in June 2016.

Instead of “wallowing” in a “self-hating” narrative of decline, the liberal left must recognise the “free, open, post-empire Britain” built over the last 45 years, and fight to hold on to it, says Dunt.