It will destroy a whole lot of things. Like any hope of security. Tech coalitions pen open letter to Burr and Feinstein over bill banning encryption | TechCrunch
The Venn Diagram tells the story.
It goes on to point out “unintended consequences” such as compromised security being compromised for bad actors as well as good, and also that any national attempt to hamper the operation of a global industry is foolish and bound to fail and, in failing, damage the reputation and economy of the U.S. (I’m paraphrasing).