The Clipper chip was proposed by the Clinton administration as a counterterrorism measure to facilitate eavesdropping on suspects against whom the government secured a warrant. In the proposed scenario, following a court’s issuing of a warrant a suspect would have their chipset activated and federal, state, or local law enforcement would monitor the suspect’s conversations.
The Clipper chip was unsuccessful due to several factors. Online privacy advocates brought to light that the chipset’s encryption algorithm (Skijack) was not publicly examined by the encryption community. They also suggested that the device’s key escrow system itself was vulnerable to a brute force that would enable the user to encrypt conversation but deprive authorities of the ability to listen in.
In addition, Clipper chip opponents stated that if only US manufacturers were required to include the chipset, then foreign-manufactured phones would be imported resulting in the program’s failure and material damage to US wireless phone manufacturers.
"Well before smartphones were the norm, the government had envisioned placing a Clipper chip into standard cellphones that — when activated — would enable law enforcement to monitor conversations."