“It is unusual for a sitting US president to intervene directly in an election in a foreign country, and maybe risky. But then, there is nothing “usual” about Britain’s EU referendum ... Whether the country votes “remain” or “leave,” the Conservative Party will go on running the country. But British leadership in the world is very much at stake. And because it really is a matter of profound, bi-partisan, long-term US interest that Britain remain a European power and thus a world power, Obama is right to take the risk and say so."

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“If Britain leaves the EU, it would remain on the UN Security Council, of course, but that’s an increasingly meaningless body. Britain would remain in NATO, but NATO is a military alliance at a time when most of Europe’s security challenges are not strictly military but rather related to economics, policing, even to information policy—all of which are, at least in theory, within the competence of the EU. And if the EU hasn’t come up with solutions, that’s partly because Britain, with this referendum looming, has spent the past several years staying aloof.

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““None of your business” is an understandable British reaction to Obama’s visit, in other words, but it misses the point. As the “leave” camp doesn’t seem to understand, we live in an interconnected world, where events in one country necessarily affect those in others. The United States needs Great Britain to stay great, both for their sake and ours.”

Read: Why Obama is right to urge Britain to stay in the EU