In defense of the Brexit decision she now must implement, British Prime Minister Theresa May said Sunday that no "divisive nationalists" would hold up the process of exiting the European Union, and she firmly asserted that all four of Britain's constituent "nations" — England, Wales, Scotland and Northern Ireland — would Brexit together.

But the Brexit decision was fueled in many ways by nationalist sentiments, centering on perceived threats to Britain's sovereignty and many of its citizens' desires to prevent the supposed dilution of their national identity by immigrants crossing the European Union's open borders.

Just three days after her comment about "divisive nationalists," at her Conservative Party's annual conference, May espoused her own brand of nationalism — one that seems to encompass all of Britain, but excludes those who may feel as though they have multiple nationalities, or identities.

"Today, too many people in positions of power behave as though they have more in common with international elites than with the people down the road, the people they employ, the people they pass on the street," she said. "But if you believe you are a citizen of the world, you are a citizen of nowhere. You don't understand what citizenship means."

As it turns out, about half of the people "down the road" or whom one might "pass on the street" identify with the very phrase May disparaged — being a "citizen of the world" or global citizen.

In an 18-nation survey conducted by GlobeScan in conjunction with the BBC World Service that was released just over a month ago, 47 percent of Britons said they somewhat or strongly agreed that they considered themselves more as global citizens than citizens of the United Kingdom.

That number is just slightly below the 51 percent of all respondents who felt the same way. Below is a look at how respondents from each of the 18 surveyed countries responded. It is worth noting that "urban-only" samples were used in Brazil, China, Indonesia and Kenya.

The poll surveyed 20,000 people between December 2015 and April 2016, which coincides with the lead-up to the Brexit vote.

GlobeScan has been carrying out similar surveys since 2001, and this year marks the first time since then that a global majority leans toward "global citizenship." Strong upticks in feelings of global citizenship in developing countries — including Nigeria (73 percent, up 13 points), China (71 percent, up 14 points), Peru (70 percent, up 27 points) and India (67 percent, up 13 points) — were the biggest drivers of the increase.

Conversely, seven European countries in the survey have followed an opposite trajectory, dropping to a low of 39 percent in 2011 and remaining at low levels since (now at 42 percent), according to GlobeScan. It notes that this has been "particularly pronounced" in Germany, where identification with global citizenship as opposed to national identity has dropped 13 points since 2009 to 30 percent today (the lowest since 2001).

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