Gov. Howard Dean: Trump 'unmasked' failure of the Republican Party

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Speaker Paul Ryan says Trump is simply “trolling” people by threatening to revoke the security clearances of former National Security officials, as Attorney General Jeff Sessions laughs with high school students chanting “lock her up”. Former Governor Howard Dean tells Ari Melber that Trump has "unmasked" the "failure of the country and especially the Republican Party to stand up for America”.