Idioms and Expressions. "The Day that Rocked the World" is one of them. I was just thinking, 3-11 was one such day...but it was kinda literal. The "ground rocked".
Koriyama City, Fukushima Prefecture, Japan. The morning of March 11, 2011. My son crossed his junior high school gymnasium platform amid applause to receive his graduation certificate along with his other classmates, smiling into bright high school days...but that wasn't what "rocked". Several hours later a huge earthquake hit Japan, sending floor and walls into convulsions: plates were hurtled out of pantries (I saw "flying saucers" that day!) rubble and broken glass was scattered across the ground; water began pouring out from cracked pipes underground such that "ponds" were formed above ground. Needless to say, utilities were cut off for a while. The Sendai airport was destroyed. Nuclear power plants, once means of energy and income, now threatened death.