A real politician would denounce the falsehoods in the strongest terms.
FWIW, the first amendment doesn't protect defamatory speech.
In fact, the classy approach (and I believe the same thing would have held for Walker, who arguably got misrepresented by Trump the other day) would be to thank the other party for bringing up the matter, because now it’s a chance for Trump to highlight the truth, which is [etc.]
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Truth is not defamatory.
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