If it's libel and slander he should sue, but I would encourage you to look at the ads that Club for Growth ran that Trump threatened to sue them over. There is noting in these ads that is libel and slander, it is Trump in his own words. I'm just saying that it's a slippery slope if candidates sue other candidates against attack ads that don't contain libel and Donald threatened to sue Club for Growth after they aired attack ads that featured Donald using his own words.
Trump sends cease-and-desist letter to Club For Growth
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