Since 2016, the cardinal rule of Republican politics has been to defend Donald J. Trump and his allies at all costs, no matter the allegation. That appeared to change last week, when Texas lawmakers issued 20 articles of impeachment against their state’s attorney general, Ken Paxton, a powerful Trump supporter. J. David Goodman, the Houston bureau chief for The New York Times, explains what the escalating conflict in Texas indicates about tensions within the party. Guest: J. David Goodman, the Houston bureau chief for The New York Times.