Now that Britain has scheduled for June its vote on whether to exit the European Union, we find ourselves thinking of what Thomas Jefferson would do. He was the principal author of the Declaration of Independence. Even while he wrote for revolution, he rued the separation from England. It’s a sentiment that echoes across the centuries as Britons now decide whether to stand for their own freedom against European socialism.

If only the Republicans could hear the echoes. It is amazing, as we’ve oft suggested, that this referendum has been met among Republicans with little but silence. That silence obtains even after all the blunders by President Obama, who has been warning the ally with whom America has so long boasted of a special relationship that his administration would begrudge any decision in favor of leaving the European Union.

The right move for the Republicans would be to endorse the Brexit. And to say to Britain: If you are prepared to stand for your own liberty, let us encourage you with an offer to strengthen our special relationship and forge — along with such free market democracies as, among others, Canada, Australia, New Zealand, India, and Israel — a new liberty bloc. It’s an opportunity for both of us.

We understand the sentiment is not universal. Mr. Obama prefers the kind of socialism favored by Europe. So do both Hillary Clinton and Senator Bernie Sanders. Mr. Obama has gone so far as to suggest that America’s interests lie in Britain serving as a moderating influence in Brussels. His trade representative, Michael Froman, has warned that Brexit could subject Britain to the kind of tariffs America imposes on still-communist China.

“Ugly scaremongering” is how this was characterized in a column by the director of the Margaret Thatcher Center for Freedom, Niles Gardiner. Six members of Prime Minister Cameron’s own government (and Thatcher’s chancellor, Lord Lawson, and, just lately, the mayor of London, Boris Johnson) have come out for the very Brexit that Mr. Cameron opposes. Senators Cruz and Rubio have at least said (as did Governor Bush) they’d offer Britain a trade deal if it runs for freedom. But where is Donald Trump? This is a moment for the Republican candidates to step up with a major vision.

Which brings us back to the question about Jefferson. This struck us while reading Peggy Noonan’s eloquent and affecting anthology, “The Time of Our Lives.” She recalls that Jefferson was unambiguous in concluding that the breach with England was permanent. He wrote that “manly spirit bids us renounce forever” our old friends. It was also clear, however that Jefferson regretted the breach.

“We might have been a free and great people together,” he wrote in an early draft of the Declaration. Those lines didn’t make it into the final version. Yet how those words echo across the centuries in this moment when there hangs in the balance the conception of liberty that we share with Britain, a conception given some of its noblest early expression in England and Scotland.

It’s hard to imagine that Jefferson would not, were he alive today, spring to craft a structure of hope for Britain, something well short of reunion but less vague than the talk of a special relationship. How his polygraph would have been cranking out correspondence. He would know that if we fail to offer some encouragement to Britain, we may have centuries more of sadness for our kindred spirits across the Atlantic.