There is No Middle Ground on Encryption

On May 2, 2018 the Electronic Frontier Foundation wrote: "Encryption is back in the headlines again, with government officials insisting that they still need to compromise our security via a backdoor for law enforcement. Opponents of encryption imagine that there is a “middle ground” approach that allows for strong encryption but with “exceptional access” for law enforcement. Government officials claim that technology companies are creating a world where people can commit crimes without fear of detection. Despite this renewed rhetoric, most experts continue to agree that exceptional access, no matter how you implement it, weakens security. The terminology might have changed, but the essential question has not: should technology companies be forced to develop a system that inherently harms their users? The answer hasn’t changed either: no."
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Whenever you add a master key, a back door, or some other means of bypassing the security of a device you instill a weakness in that security. Simply put having a way to bypass security makes that security less effective.

Once a way to bypass encryption is added to a device, it is only a matter of time before someone is able to hack it, or until some "authorized user" can be paid off to misuse his or her authorization to that master key or backdoor.

Adding a back door to our encryption does nothing to prevent criminals from using encryption that doesn't have a back door. If US encryption contains back doors, then get your encryption from Russia, or Germany, or Serbia, or the Czech Republic. Use open source encryption, such as Open PGP or various implementations of  AES-256 that does not contain a back door.