A smoking gun. Allegations of fake news. Adversarial press coverage that made it impossible for embarrassed lawmakers to sweep a scandal under the rug.The political sensation that came to be known as the Credit Mobilier scandal unfolded in the era of the telegraph and the steam engine. But it included elements of every Washington scandal, from Teapot Dome and Watergate to Whitewater and the allegations that the Trump campaign colluded with Russia.