General Hayden was recently on Sam Harris' podcast and he briefly explained the 'retroactive collection' concept-

https://www.samharris.org/podcast/item/privacy-and-security

I'd say his arguments appear clear and convincing, even to a skeptic like myself. I wonder what can be done to counter his seemingly perfect narrative so Americans can be rightfully concerned about what's happening.

To be clear, I don't believe Hayden, he is likely lying about aspects of it, these systems will inevitably be used in the future for regular law enforcement purposes and the previous abuses by NSA staff is understated. Plus, it is unequivocally illegal and a violation of natural rights. And just a bad idea which will lead to a dangerous future.