Former Senate Majority Leader Bill Frist (R-Tenn.) warned Republicans against continuing their "assault" against Robert Mueller, writing in an op-ed Friday that the GOP must let Mueller continue his investigation. In an opinion piece for The Washington Post, the former Tennessee Republican urged Republicans to fight for the "rule of law," even if it meant going up against the Trump administration. "I am also a Republican because I believe in the rule of law. Republicans must fight for that principle today — even if it means pushing back against a Republican administration," Frist wrote. "It isn’t easy to tell a...