Ramesh Ponnru makes a good case that the U.S. shouldn’t take sides in the U.K. debate over “Brexit”:
The second point is that we aren’t likely to sway the British by making a case based on our interests, either. The referendum involves some of the most profound interests a nation can have. Many Britons see the European Union as a threat to their economy, their sovereignty, even their way of life. We cannot convince them they are wrong about these issues, and it is not our place to try. And it is not reasonable to ask people who have these concerns that they should look past them because we find their membership in the EU useful to our own foreign policy.
Just as it was inappropriate for the president to say anything about the referendum on Scottish independence (he endorsed the unionist position), he should refrain from publicly picking a side in the debate over withdrawing from the EU. Obama has already stated the U.S. position on Britain’s membership in the EU in the past, but to do so again when the referendum is just a few months away would be a mistake. It’s also a mistake to condition our relationship with the U.K. on their relationship with the EU. The U.S. and Britain were allies before there was a common market, and long before the existence of the modern EU, and if most people in Britain no longer wish to remain part of the EU that should not affect our relations with them.
If there is one thing that won’t go over well with people in the U.K. on both sides of the debate, it would be a statement from Washington trying to influence or dictate what they should do. While many Euroskeptics may value the relationship with the U.S., they won’t respond well to being lectured or threatened by our government. Even if it were obvious that “Brexit” was bad for U.S. interests, any interference in the referendum from our government would likely backfire, and it’s not at all obvious that “Brexit” would actually harm any U.S. interests. It is likely that a vote to leave the EU would trigger another vote on Scottish independence, and withdrawal from the EU would make it more likely that Scotland would vote for independence this time, but ultimately that is a constitutional question to be worked out inside the U.K. and should not be Washington’s concern. The U.S. should commit itself to maintaining good relations with the U.K. and the EU no matter what happens in the referendum in June, and that should be the only position our government needs to take.