When the Cutty Sark regularly plied the oceans of the world in the 19th century, no one doubted where Britain was moving. The tea clipper was just a single part of the massive political and economic might of the forward-looking British Empire.

Today, the Cutty Sark now sits on display on the banks of the Thames in Greenwich. Keith Merritt stands admiring the ship, where he chose to bring his six-year-old grandson on his first visit to London to see “all the good bits of where we were.” But the engineer can’t help but lament that Britain in 2014 is not gazing outward, but increasingly inward, thinking smaller instead of big.

Within three years, Britain faces two major tests that could radically diminish its size in the world, both literally and figuratively.

The first comes in September, as Scotland is scheduled to vote on whether it wants to remain part of the United Kingdom, to which it has belonged since 1707.

The second could come in 2017, when, under pressure from anti-European Union populists, British Prime Minister David Cameron has promised to hold a referendum (if he wins reelection first) on whether Britain should remain in the EU.

Both referendums are distinct exclamations of long-simmering sentiments about sovereignty; but there is interplay between both. A “yes” for either would mark a new chapter in British history. Together, they’d alter Britain’s diplomatic weight, military endeavors, trade relations, and place in the global order.

“If there was a yes for withdrawal and a yes for Scottish independence, it will have a major influence on this country’s standing in the world,” says Michael C. Williams, a member of the House of Lords, former UN undersecretary general, and fellow at the Chatham House think tank in London. “This would much diminish the country in every sense."

No longer United?

Scottish independence has been pondered for the last 300 years. But a referendum was made possible with the surprise overall majority that the Scottish National Party, led by Alex Salmond, won in 2011. He has appealed not just to centuries of nationalism and nostalgia, but by emphasizing Scotland as a more caring social democracy based on Scandinavian values, not the free-market forces around which Westminster revolves. On Sept. 18, Scottish adults will be asked: “Should Scotland be an independent country?”

Polls have consistently shown the “no” vote in the lead. Scotland already enjoys wide autonomy, including its own parliament since 1999. Only about a third of voters have said they intend to vote “yes,” but that has been narrowing as the vote nears, and significant undecided voters make the poll a wildcard. Mr. Cameron is visiting Scotland today to bolster support for the "no" side.

The repercussions of “yes” are unclear for both Scotland and Britain. Salmond has promised to continue using the pound, after once advocating for the euro, but the three major British political parties recently came together in rare unity to say no. It is also unclear what would happen procedurally for Scottish membership in the EU or NATO, and what the fate would be of oil in the North Sea and British nuclear submarines based in Scotland. Most in Britain have said they don’t want Scotland to leave. An Ipsos Mori poll, commissioned by the British think tank British Future, showed that 47 percent of adults across Britain felt the UK would be weaker without Scotland.

At the same time, opinion polls have recorded a growing “English” identity that is challenging the status quo, both for the English relationship with Scotland and the EU, says Glenn Gottfried of the Institute of Public Policy Research who co-authored a report called "England and its Two Unions."

“There is a growing discontent in England with the constitutional arrangements both with Scotland in the UK and Europe,” he says.

The edge of Europe

It is largely coincidence that Britain debates leaving the EU while Scotland debates leaving the UK, but it has put the ruling classes in an awkward position as they wish to convince Scotland that it’s better off as part of a larger union at the same time that it addresses voters who wish to leave the much larger union of the EU.

And they do impact one another. Some argue that if the UK Independence Party (UKIP) does well in elections, as is expected in European parliament races in May, it could add fuel to Scotland’s independence supporters, who are more pro-EU than England. Similarly, Thomas Raines, a Europe expert at Chatham House, says that if Scotland were to leave Britain, it leaves a weaker pro-EU union overall.

Ambivalence about Britain’s membership in the EU, which it joined in 1973, has been present for decades, more strongly felt among older Britons and those who have been left behind in the global economy. But the plans for a referendum came under pressure from the rise of UKIP, led by Nigel Farage. Last year, Mr. Cameron promised to renegotiate Britain’s membership in the bloc and then organize an in-or-out referendum.

This referendum is much tighter than the Scottish one, with voters split on the issue, though a recent Pew poll showed a significant bump in the number of Brits who now say they want to stay in the EU, 50 percent, compared to 41 percent who wish to leave. And while still hypothetical, the debate about what’s to gain or lose is growing. One group, the free market Institute of Economic Affairs, recently handed out a prize to the best blueprint for a so-called “Brexit” to get society thinking about an “out” scenario, says Philip Booth, editorial and program director at the institute. The winner, a British diplomat in the Philippines, says the economy could grow by 1.3 billion pounds [$2.2 billion] if it left the EU.

Others, like Lord Williams, say far more is at stake than economics. In the worst case scenario, he says, a yes for both could call into question Britain’s permanent seat at the UN Security Council.

Get the Monitor Stories you care about delivered to your inbox. By signing up, you agree to our Privacy Policy

Sunder Katwala, the head of British Future, says that whether Britain is better off out of the EU or without Scotland are questions that signal an unresolved national identity. That both referendums come to heads now, says Mr. Katwala, “means that British identity is in flux, that it’s up for grabs.”

As Mr. Merritt, in front of the Cutty Sark sees it, England “as an island” would not survive, nor would Scotland survive alone either. “There is no country in the world that can do that,” he says. “Everyone needs everyone else.”