Parts of that whole expose were covert. In the case of Google we know by tapping fiber connections that they had between data centers (as sseth mentioned, using

Parts of that whole expose were covert. In the case of Google we know by tapping fiber connections that they had between data centers (as sseth mentioned, using foreign intelligence peers to do an end run around legal protections), which was on Google owned fiber, theoretically entirely "in-house", so Google transferred it unencrypted. I believe they called this operation "Muscular". After the fiasco Google started assuming everything was hostile.