The United States may still have the “special relationship” with Britain that Winston Churchill vaunted some seven decades ago.
But increasingly that relationship has mattered to the US because of the influence Britain wielded inside America’s bigger and more consequential transatlantic partner, the European Union.
Now Brexit, Thursday’s British referendum on whether to exit the EU, could remove that reliably US-friendly voice from EU deliberations. That would accelerate Britain’s already decreasing importance to the US, some transatlantic experts say, and also – over time – diminish US influence in Europe.
When the EU takes up issues of importance to the US “what we need on the inside is a determined ally and advocate, and that’s frequently been the UK,” says Kristen Silverberg, who served as US ambassador to the EU under President George W. Bush.
For example, she cites two recent issues of vital importance to the US – sanctions on Iran over its nuclear program, and sanctions on Russia over its invasion of Crimea and aggression in Ukraine. In both cases, a resolute Britain helped sway a wavering EU to the US position in both cases.
With Brexit, she adds, “We’d lose an advocate and ally.”
Indeed some transatlantic experts say Russian President Vladimir Putin’s strong public support for a “yes” to Brexit suggests his keen awareness that it would weaken the EU’s resolve to stand up to Russia and renew sanctions next month, and weaken the transatlantic partnership more broadly.
President Obama seems to foresee a “yes” vote as detrimental to Western interests as well. In April he visited London to make the case for Britain’s continued EU membership – and to try to boost British Prime Minister David Cameron’s efforts to get a “remain” vote out of his constituents.
Britons have benefited in terms of trade and jobs from being inside the EU, Mr. Obama said, while Britain’s friends have benefited from having the British perspective brought to EU discussions on everything from transatlantic trade to intelligence sharing.
“It leverages UK power to be part of the European Union,” Obama said at a London press conference. Being a member of the EU doesn’t moderate “British influence in the world, it magnifies it.”
With Brexit, Britain risks being eclipsed in Washington by the EU's rising power, Germany.
“Britain will be even more peripheral to US foreign policy” if it decides to pull out of the EU, says James Goldgeier, dean of American University’s School of International Service in Washington. “Its decline as an international power will become more apparent over time,” he adds, and in turn will “make the special relationship less special.”
Debate over Brexit's impact on global economy
Beyond the national security implications of Britain leaving the EU are the international economic ramifications, which would almost certainly ripple across the Atlantic.
Most international economic institutions and economists warn that a Brexit would lead to a plunge in the value of the British pound and more long term would mean lower growth rates for Britain, which in recent years has been one of Europe’s few economic bright spots.
But some experts say that perhaps the biggest economic risk Brexit poses to the global economy (and thus to the US) is the heightened level of uncertainty it would engender.
“This already feels like a very risky time economically,” says Ambassador Silverberg, who is now managing director of the Institute of International Finance in Washington. Citing the US presidential election campaign and doubts about China’s economic trajectory, she adds that the “existing uncertainty would only grow with the UK deciding to leave the EU.”
Despite substantial support in the US for Britain remaining in the EU – led by the White House – some conservative voices take the opposite view, insisting both Britain and the US would be best served by a “yes” to Brexit.
Brexit “does open up the possibility for the UK to go in a much more classically liberal economic direction,” denoted by smaller government and less regulatory burden than the EU economic model, says Theodore Bromund, an expert in Anglo-American relations at the Heritage Foundation in Washington.
Citing London’s economic reforms in recent years as the reason Britain has outperformed much of the rest of Europe, Dr. Bromund says Brexit “opens the possibility to move faster in this direction.” And the stronger Britain is economically, he adds, the better ally Britain is to the US.
Bolton: Free Britain of EU's 'weak resolve'
From a strategic standpoint, others insist that the US is better off with Britain outside the EU and rechanneling its cooperation on foreign policy and national security concerns through NATO, which includes the US.
One American cheerleader for Brexit is John Bolton, the former US ambassador to the United Nations during the Bush administration, who insists that a Britain freed from the “weak resolve” of the EU will be a stronger US ally.
But Ambassador Bolton has said there is another key reason Americans should support Brexit: Without Britain, the EU is much less likely to pursue its stated goal of a “common foreign and security policy,” which he believes would stand separate from both NATO and the US.
“Although innocuous sounding,” an EU common foreign and security policy would mean “an EU international policy separate and apart from America … a ‘separate pole’ from the United States in a ‘multipolar’ global order,” Bolton wrote in a recent column published in the Pittsburgh Tribune Review.
In other words, to keep NATO strong and Europe a US ally rather than competitor, support Britain leaving the EU.
Such thinking may reflect Britain’s traditional concerns over lost national sovereignty and ambivalence towards Europe, but for many specialists in transatlantic relations, the certain down sides for the US in a Brexit outweigh the potential positives.
“There are arguments for Brexit, but they do not outweigh [the fact] that the EU is more like-minded with the US with UK participation,” Silverberg says. “The Europeans are frustrating, we have many disagreements with them,” she adds, “but I still will take them over other allies we have.”