Walid Saadaoui and Amar Hussein had big plans — so big that children in the United Kingdom would have read about them in their history books and memorized their names, whether they would have been lionized as heroes or excoriated as villains. To their everlasting disappointment, however, their rendezvous with destiny never happened. Their big plans ended up being disrupted before they had a chance to carry out what has been called “the deadliest terrorist attack in UK history.” Sky News reported Tuesday that Saadaoui, 38, and Hussein, 52, have just been found guilty of plotting a jihad massacre with...