Miffed by the agency’s initial scoring of the AHCA in March, Missouri Senator Roy Blunt derided the CBO as “notoriously bad” at predicting market outcomes. “They're sometimes not even very good at adding and subtracting,” he snarked. Health and Human Services Secretary Tom Price grumped that “the CBO report’s coverage numbers defy logic.”

White House budget director Mick Mulvaney has been even harsher, dismissing the agency’s relevance altogether. The CBO’s time “has come and gone,” Mulvaney suggested to the Washington Examiner in May, ominously noting, “You can have a government without a Congressional Budget Office.” Trump fanboy Newt Gingrich has been peddling a similar message, calling the CBO “corrupt,” “dishonest,” and “disgustingly wrong” and advocating its total abolition. (To be fair, Gingrich has loathed the agency since his days in Congress.)

All this hating on the CBO is more than a little rich, given that Republicans recruited its current chief, former Bush 43 adviser Keith Hall, just two years ago. Among those most intimately involved in the selection was then-Representative Tom Price, who gushed of Hall, “His vast understanding of economic and labor market policy will be invaluable to the work of CBO and the important role it will continue to play as Congress seeks to enact policies that support a healthy and growing economy.”

But (with props to Taylor Swift) all that mad love has turned to seriously bad blood, putting Hall and his people in a tough spot.

The CBO is supposed to stay above the political fray, serving as an independent, nonpartisan source of analysis. Both teams must be able to trust the agency’s neutrality, or its work indeed becomes worthless.

Of course, politicians being congenital whiners, the CBO takes its share of abuse. Not infrequently, the agency comes out with numbers that one or the other team dislikes. That team loudly trashes the numbers. Outrage is voiced, chests are thumped—then everybody hunkers down and the show grinds on.

But when officials start taking issue, not with a particular analysis or particular staff members, but with the agency’s very purpose, it’s time to get nervous.

Mulvaney is technically correct: You most certainly can have a government without a Congressional Budget Office. The legislative branch of that government, however, would be even less equipped to deal with data and complex analyses than it currently is. Which is saying a lot, given that lawmakers have been chipping away at their own institution’s capacity for decades.

Everyone loves to bash Big Government. Small wonder then that funding for a range of congressional support services has been slashed since the 1970s. Committee budgets have been cut, meaning staffs are smaller—and smart staffers decamp for more lucrative gigs the second they have an ounce of experience. As for support offices, the Brookings Institution notes that “the Congressional Research Service, the Government Accountability Office, and the Congressional Budget Office have lost 45 percent of their combined staffs from 1975 to 2015.”