The evidence seems to show that open source crypto is more likely to be secure. The Dual_EC_DRBG [1] thing is a good example where the NSA was desperate enough

The evidence seems to show that open source crypto is more likely to be secure. The Dual_EC_DRBG [1] thing is a good example where the NSA was desperate enough to actually try to hack an algorithm and then was immediately caught at it. That known dodgy algorithm was then used in commercial crypto products for 7 years. The open source crypto community could just avoid it. Snowden used an open source implementation of PGP based on his knowledge of the NSA's capabilities at the time. He did not go shopping at the crypto store. [1] https://en.wikipedia.org/wiki/Dual_EC_DRBG https://en.wikipedia.org/wiki/Dual_EC_DRBG