Down in the polls, Donald Trump is trying to revive his campaign by identifying with another recent populist revolt that defied the odds: the campaign for the United Kingdom to leave the European Union.

Last week Trump tweeted, "They will soon be calling me Mr. Brexit." This week, Trump flew in outgoing UKIP leader and Brexit architect Nigel Farage to campaign with him.

There are some similarities between Trump's campaign and the Brexit movement, on immigration, working class unemployment and nationalism.

But there's also a big difference. Brexit was fundamentally about sovereignty and self-government — the idea that Great Britain should be governed by Britons, not by non-British bureaucrats in Brussels. The slogan of the Leave campaign was: "Vote Leave. Take Control."

Local sovereignty and self-government aren't what Trump, whose proposals would concentrate more power in the executive, is promising.

And there's another difference, one that the Washington Examiner's Dan Hannan, himself a member of the European Parliament and a leading Leave campaigner, pointed out in his most recent column. Hannan writes that while the Brexit campaign was upbeat, civil and progressive in the best sense (it supported global markets and free trade as opposed to being trapped within a protectionist Europe), Trump's campaign has been angry, nasty and insular. Whereas Trump's slogan is "Make America Great Again," The Brexit campaigners' was, in essence, "We think our country is pretty great, thank you very much."

Hannan personally made clear, in every television appearance he made, that a "Leave" vote was about allowing Britain strengthen its economic ties to rest of the world, something it could not do unilaterally as long as it remained within the EU.

"I worked for 26 years to make Brexit happen," Hannan writes. "I wrote the book on why Britain should leave the EU. I appointed the campaign director who won us the referendum.

"Mr. Trump, you're no Mr. Brexit."

Daniel Allott is deputy commentary editor for the Washington Examiner