Other than as a notch on your valiant keyboard, Star Moron Firebrand Gary, what difference does it make?
Before Andrew Johnson was impeached he was President, with the full authority of the office of President. And after he was retained in office Andrew Johnson had the full authority of the office of President.
Before Bill Clinton was impeached he was President, with the full authority of the office of President. And after he was retained in office Bill Clinton had the full authority of the office of President.
Before Donald Trump was impeached he was President, with the full authority of the office of President. And since he was retained in office Donald Trump has had the full authority of the office of President.
Richard Nixon was not impeached, Star Moron FireIgnoramus Gary.