Congressional leadership isn't ready to take on the fact that the occupier of the Oval Office possibly got there by colluding with a foreign adversary or that every day he's been in office he's been in violating the emoluments clause in the constitution. No, leadership has no interest in delving into the legitimacy of this president and possibly undermining the Republican majority. But they do care about turf. Specifically, sending the message to the administration that if government is going to be reorganized, they're the ones in charge. Slipped into the omnibus spending bill Trump was so pissed about signing last week is a warning to Trump.
Section 740 of the 2,232-page document makes it clear, as Bloomberg Law previously reported, that Congress, not Trump, is in charge. "None of the funds made available in this or any other appropriations Act may be used to increase, eliminate, or reduce funding for a program, project, or activity as proposed in the President’s budget request for a fiscal year" unless Congress approves, according to the omnibus legislation. […]
"Make no mistake about it: This is a direct shot across the administration's bow," said Donald F. Kettl, a University of Maryland professor of public policy. "It's not only a warning that the administration should not proceed with the reorganization plans floated by senior Cabinet officials. Even more fundamentally, it's a statement about the separation of powers: Congress creates agencies, it creates programs, it funds their execution." […]
"It's remarkable, in fact, that this tough language comes from the Omnibus bill that was led by the Republicans," Kettl added in an email. "The majority clearly is most interested in asserting its institutional role, even at the expense of potentially tangling with the West Wing."
To a point, of course—they're not going to take on the institutional role of being a check on the executive if it means impeaching a Republican president. The background here is important, though. Early last year, the administration issued its "Comprehensive Plan for Reorganizing the Executive Branch" which lays out Trump's intention to "eliminate unnecessary agencies, components of agencies, and agency programs," and in fact his budget called for the elimination of 19 small agencies.