shake the foundations of (something)
To impact something in a way that affects its very essence, especially concerning its values or beliefs. The death of her son shook the foundations of her beliefs. The election of the outsider candidate shook the foundations of the party, and led to a lot of soul-searching among its members.
shake/rock the ˈfoundations of something
, shake/rock something to its ˈfoundations
cause people to question their basic beliefs about something: This issue has shaken the very foundations of French politics.