For years, Jack Smith — the prosecutor with the best chance of putting President Donald Trump in prison — was an elusive figure. His work was cloaked in secrecy and his voice was seldom heard aloud, save for a few choice utterances at carefully scripted news conferences. Public sightings were rare, and he was best known by a single scowling image from a 2020 appearance at The Hague. Thursday morning, however, Smith's low profile will disappear when he becomes one of the most-watched people in Washington.