Here's a few hints:
— It happened at 9:02 am local time.
— It killed 168 people.
— It happened in the Murrah Federal Building in a city in the Great Plains.
— The building was targeted by conservative white-supremacist anti-government types who have ideological connections to groups and individuals that form the underpinnings of many extant right-wing movements.
— George W. Bush will very likely not say a word about it today.
Figured it out yet?