Impeachment is a political process. And judging the process strictly on political grounds, the impeachment of President Trump hasn’t been a success for Democrats. After all, House Speaker Nancy Pelosi and Rep. Adam Schiff haven’t gotten any closer to convincing a single Senate Republican to remove the president. It’s highly probable that a Senate trial run by Republicans, with new witnesses and evidence, would further corrode the Democrats’ case. Liberals will pretend that Senate Republicans are members of a reactionary Trump cult, but if there had been incontrovertible proof of “bribery,” a number of them would be compelled to act...