I have a university colleague who has a son-in-law that works for the NSA outside of D.C. that does this. According to him and what his son-in-law has claimed and asserted, yes, indeed they have the capability.
they no doubt intercept and store all packets along the fiber backbone.
the question is: for how long do they store them? since the beginning of the internet?
you all have to remember the internet was created by the military and no doubt at least all early communication was logged.