In the 1870s in the United States, in the aftermath of the impeachment of President Andrew Johnson and his near-removal from office, it was speculated that the United States, too, would move from a presidential system to a semi-presidential or even parliamentary one, with the speaker of the House of Representatives becoming the real center of government as a quasi-prime minister. This did not happen and the presidency, having been damaged by three late nineteenth and early twentieth century assassinations (Lincoln, Garfield and McKinley) and one impeachment (Johnson), reasserted its political dominance by the early twentieth century through such figures as Theodore Roosevelt and Woodrow Wilson.