However, sources and methods are the central question when it comes to investigating the investigators. So far as methods are concerned, what we know about them already are hardly worth being classified. They involve a basic counterintelligence technique, getting people to talk. In the Carter Page case, the target was a marginal character on the periphery of the 2016 Trump presidential campaign. This is not exactly on the level of the previously classified methods revealed by Edward Snowden.
But if there were some highly technical, super secret surveillance methods being used against others, including Trump himself, it is imperative that they be revealed. The notion that the U.S. government was ordered to use such advanced tools against a major party presidential campaign or a president himself is to say the least troubling, and potentially a criminal abuse of power.
Sources, likewise, should not remain concealed. Their identity is the central question of the investigation. Republicans maintain that the Carter Page FISA warrant was almost entirely based on the discredited Fusion GPS “Russia dossier,” which was bankrolled by the Clinton-run Democratic National Committee and the Clinton campaign.