In 1994, Bill Clinton signed CALEA into law. The Communications Assistance for Law Enforcement Act requires every US telecommunications network to be designed around facilitating access to law-enforcement wiretaps. Previous to CALEA, telecoms operators were often at pains to design their networks to *resist* infiltration and interception.
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Even if a telco didn't go that far, they were at the very least indifferent to the needs of law enforcement, and attuned instead to building efficient, robust networks.
Predictably, CALEA met stiff opposition from powerful telecoms companies as it worked its way through Congress, but the Clinton administration bought them off with hundreds of millions of dollars in subsidies to acquire wiretap-facilitation technologies.
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