Story highlights McTernan: Facts don't matter -- emotion does. We learned this the hard way in the UK

If Clinton doesn't start taking on Trump directly on a more visceral level, she may spend the rest of her life regretting it, he says

(CNN) If I learned one lesson from the referendum on Britain's membership of the European Union that I would like to teach Hillary Clinton, it's this: don't take a knife to a gun fight.

It is a cliche that politics is a contact sport, but like most clichés, it contains a kernel of truth. Elections are brutal -- and they should be: the winner is the person who ultimately wields power. That means that you have to fight at least as hard as your opponent. Again that makes sense: if you won't fight for your own job, why should voters believe that you would fight hard for theirs?

Someone seems to have sent the Clinton campaign the pro-EU Remain campaign's playbook for the Brexit referendum. Every gutter-trawling gaffe, error and insult from Donald Trump is met with a bloodless rebuttal which outlines what Clinton's campaign sees as the obvious: based on cold, hard facts, Trump is less suitable to take the office of President than Clinton

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But the Presidential campaign is not some academic seminar. Nor is it a game in which a 10 point plan beats no plan by 10 points to nil. The patient accumulation of facts as the basis for rebuttal doesn't work.

Facts don't matter - emotion does. We learned this the hard way in the UK during the Brexit referendum. Quiet reasonableness didn't cut it. Making the true and factual case that immigration is good for the economy and that globalization has benefited everyone by increasing their wealth wasn't enough. Not nearly enough.

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