Mr Trump for months mocked what is known officially as a Sensitive Compartmented Information Facility, or SCIF, where House Democrats and Republicans for weeks late last year heard from current and former Trump administration officials about just what the president wanted from Ukrainian leader Volodymyr Zelensky during a 25 July phone conversation.
Now the world's most famous safe space, the room on the bottom floor of the Capitol Visitors Centre designed to allow administration officials and politicians from both parties to discuss highly classified state secrets was described by the president as the House conducted its probe as a den of shady shenanigans by Mr Schiff and his House Democratic colleagues.
White House officials and GOP lawmakers backed him up, describing the room built with funds approved by Democratic and Republican members alike as a "dungeon" and a "basement bunker". White House Press Secretary Stephanie Grisham last year called Mr Schiff nothing but a "basement blogger".
But they all were taking their cues from Mr Trump. The transformation, at least in conservative circles, of a room designed to safeguard America's national security into a hotbed of partisanship and the anti-Trump movement is merely the latest example of how the president has brought his unique brand of slash-and-burn marketing to the Oval Office.
White House counsel Pat Cipollone borrowed his client's strategy of trying to use the secure room's basement location to describe it as the perfect space for Democrats to continue trying to kick the New York businessman and former reality television star out of the executive mansion.
Mr Cipollone lauded his boss for ordering the release of his 25 July call with the Ukrainian president, saying "how's that for transparency?" (The White House's own document, however, notes it is merely a summary of the call and not a verbatim transcript. Trump and his surrogates continue falsely calling it a transcript.)
Then the White House's top lawyer went full Trump, saying Schiff oversaw his part of the Democrats' investigation "in a basement of the House of Representatives".
"The president was forbidden from attending. The president was not allowed to have a lawyer present," Mr Cipollone said on the Senate floor. "In every other impeachment proceeding, the president has been given minimal due process. Nothing here. Not even Mr Schiff's Republican colleagues were allowed into the SCIF."
With the latter statement, Mr Cipollone echoed his client in another way: He uttered a false statement. The Washington Post's Fact Checker staff concluded Mr Trump uttered or tweeted 16,241 false or misleading statements during the first three years of his term.
Transcripts of those Intelligence Committee closed-door sessions with current and former Trump administration officials – as well as hours of video footage showing them entering – show some House Republicans did join Mr Schiff in the secure basement room.