You&#x27;re arguing for an impossible thing, a crypto system that <i>exactly one</i> third party can intercept.  If it&#x27;s based on a key and the key leaks, it would destroy the modern economy.<p>If it&#x27;s based on requiring a specific amount of computation, the neighborhood despot buys a billion dollars of computers instead of feeding the people and destroys the modern economy.<p>If more than one government requires such interception capabilities for a single transaction, and the communicating parties involved don&#x27;t trust all the governments involved, they won&#x27;t communicate which will destroy the modern economy.<p>If, magically, none of the previous scenarios play out, anybody who wants to communicate securely will have the enormous burden of complying with the regulations of all of the involved governments, slowing down commerce and innovation, and potentially destroying the modern economy.<p>If there&#x27;s a government key server that dispenses a public key for government snooping and it goes down&#x2F;a competing government redirects to its own key&#x2F;DNS or BGP is poisoned&#x2F;etc. then someone else gets all the traffic and destroys the modern economy.<p>Beyond the economy it&#x27;s a matter of trust.  For the relatively small benefit of a very slight (or even zero) reduction in terrorist incidents, there&#x27;s simply nobody who can be trusted with the power to snoop on everything.