It gets worse

Andrew McCarthy has a long piece that disembowels the Schiff memo: "The Schiff Memo Harms Democrats More Than It Helps Them."

There's "Heavy Reliance on Steele dossier confirmed" and "Concealing the Dossier’s Clinton-Campaign Origins" but I did not know this part about the rules of the FISA court:

So . . . here’s the question: When Steele brought the FBI his unverified allegations that Page had met with Sechin and Divyekin, why didn’t the FBI call Page in for an interview rather than subject him to FISA surveillance? Lest you wonder, this is not an instance of me second-guessing the Bureau with an investigative plan I think would have been better. It is a requirement of FISA law.
When the FBI and DOJ apply for a FISA warrant, they must convince the court that surveillance — a highly intrusive tactic by which the government monitors all of an American citizen’s electronic communications — is necessary because the foreign-intelligence information the government seeks “cannot reasonably be obtained by normal investigative techniques.” (See FISA, Section 1804(a)(6)(C) of Title 50, U.S. Code.) Normal investigative techniques include interviewing the subject. There are, of course, situations in which such alternative investigative techniques would inevitably fail — a mafia don or a jihadist is not likely to sit down with FBI agents and tell them everything he knows. But Carter Page was not only likely to do so, he had a documented history of providing information to the FBI.

Emphasis in original.  So why was Carter Page subjected to secret government surveillance through the FISA court?  As McCarthy notes, it seems likely that it was to gather up Page's present and past correspondence with the Trump campaign.  Since the Steele's Russian provocateurs had falsely claimed that Page had engaged in a collusion plot, this fake piece of evidence - paid for by the DNC - was used to spy on Trump by way of Page.