Washington • If Donald Trump were to tweet that 9 is a prime number, that Minneapolis is in Idaho, and that the sun revolves around the Earth — “Make Earth Great Again!” — would even five Republican senators publicly disagree with even one of the tweets? This matters in assessing the wisdom of beginning an impeachment process against the president. If every senator in the Democratic caucus were to vote to convict Trump in an impeachment trial concerning articles voted by the House, 20 Republicans would have to join them to remove him from office. So, the likelihood that he will not finish his term is vanishingly small.