The British voters' stunning setback for Prime Minister Theresa May's Conservative Party will result in a hung Parliament, and may hang up Brexit negotiations and even the Western alliance.

May's miscalculation may also cost her with her colleagues, who could press for a new leader. But for now she looks likely to cobble together an incredibly slender majority by partnering with the Democratic Unionist Party of Northern Ireland. But the DUP may not completely agree with May's call for a "hard Brexit" stance in its impending negotiations with the European Union, meaning that the divorce proceedings could be even more messy than anticipated, adding further uncertainty to a country contending with economic doubts and a sharply divided society.

This was the very outcome May was trying to avoid by calling a snap election to strengthen her hand regarding Brexit. But she ran a clumsy campaign, and as a result the Conservatives lost their outright majority, winning a projected 318 seats from its previous 331, and 10 short of a majority. Conversely, the Labour Party outperformed expectations, picking up 30 seats for a total of 262 in the 650-seat House of Commons, and its leader, leftist Jeremy Corbyn, emerged as a clear political winner.

Corbyn opposed Brexit, but predicated his campaign on May's leadership and his support of social spending, among other domestic concerns. But because Corbyn will not be prime minister, a fundamental rethink of Brexit is unfortunately unlikely.

Internationally, the election outcome may further complicate relations with leaders whose nations will remain in the European Union, especially since the continent's most consequential politicians — German Chancellor Angela Merkel and new French President Emmanuel Macron — are staunch advocates for an even more integrated Europe.

While Britain's NATO status wasn't an issue, the disunity isn't good at a time when the threat from Russia and transnational challenges like terrorism, cybercrime and conflict triggered from climate-change disruptions make the alliance more relevant than ever.

As for the "special relationship" between the United States and the United Kingdom, it was already an issue, and indeed President Donald Trump's insensitive response to the recent London terrorist attacks and his labeling himself as "Mr. Brexit" may make it harder for a politically wounded May to tighten transatlantic ties.

"Britain will be weaker — definitely weaker," Frances G. Burwell, a distinguished fellow at the Future of Europe Initiative at the Atlantic Council, told an editorial writer. "Britain is going to be a diminished power. And that's unfortunate, because there are things going on in the world where we could use their help, especially diplomatically, but the prime minister currently doesn't have the credibility."

It's important that the loss of credibility doesn't erode the West's credibility, too. Britain's political upheaval is just the latest test for the ability of the U.S. and Europe to lead in a turbulent world.