David M Jackson

USA TODAY

Shocked at the United Kingdom's decision to leave the European Union, American political observers can't help but wonder: Will this help Donald Trump?

Trump certainly thinks so.

Saying "people want to take their country back," the Republican presidential candidate told a news conference Friday in Scotland, "I really do see a parallel between what's happening in the United States and what's happening here."

Trump says U.K. vote to leave EU is a 'great thing'

Although there are good signs for Trump in the "Brexit" vote, there are also signs it won't make much difference.

"Nobody really knows," Trump himself acknowledged.

Among the good signs for Trump in the wake of the Brexit:

• It shows what potent issues immigration and free trade have become for voters who are struggling economically; these issues are at the heart of the Brexit and the Trump campaign.

• British politics have been known to presage developments in their former colony. Nearly four decades ago, conservative leader Margaret Thatcher overturned the British political establishment by becoming prime minister in 1979 — one year before Ronald Reagan did much the same thing by winning the American presidency.

• Nationalism has re-emerged as a major political force in politics worldwide, and that bodes well for a candidate whose slogan is "Make America Great Again."

• Democratic candidate Hillary Clinton and President Obama supported British membership in the European Union; are they misreading the American political mood as well?

There are also signs the Brexit won't matter in the USA in November:

• This was an election unique to Europe, with few ramifications for the USA.

• Markets in the USA and other countries are likely to take an economic hit over the Brexit, at least in the short term, and there will be other unforeseen consequences; the blowback could hurt Trump-style politics.

• Elections are about individuals, and Trump and Clinton are already well-known by American voters.

New polls show Trump slipping behind Clinton. Though the New York businessman is competitive in places such as Pennsylvania and Ohio, he struggles in must-win Republican states such as Florida, Arizona and Utah.

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First Take: Stunning 'Brexit' victory calls EU future into question