(Bloomberg Opinion) -- The confrontation between Donald Trump and the House of Representatives -- in which Trump is doing everything he can to block the House’s normal oversight powers -- has me thinking about impoundment.

That’s an old Nixon-era controversy, in which President Richard Nixon tried to not spend – “to impound” – money that Congress had appropriated for some programs Nixon opposed. He wasn’t the first president to do it, but the scope and scale of what he tried to do were beyond anything that his predecessors had attempted.

Eventually, Congress made it clear it wouldn’t stand for this, in part by passing a new budget law in 1974. That same Congress also passed the War Powers Act after Nixon had bypassed Congress in expanding the Vietnam War into Cambodia. Again, other presidents had done similar things, but Nixon took it a step further. 

All this is relevant now because it gets to why impeaching Trump might be necessary. Nixon didn’t just commit crimes. Many presidents have done that. The real breaking point was that Nixon simply refused to play by the rules set forth in the Constitution. And Trump appears to be on the same course.

Of course, Nixon had done a lot of things that were plainly illegal, both in the constellation of activities lumped together under “Watergate” and in the obstruction of justice in covering up those acts. And there was the realization among Nixon die-hards, when the “smoking gun” tape demonstrated the president had directly lied to them, that he just couldn’t be trusted at all and was willing to make his supporters look foolish when they vouched for him.

But Congress’s decision to push ahead with impeachment was also motivated by Nixon’s fundamental rejection of Congress’s own legitimacy. I’ve quoted the late political scientist Nelson W. Polsby on this point before:

In [Nixon’s] view, his election conferred not only an extraordinary measure of legitimacy upon him, but also a kind of illegitimacy upon many of the very people with whom a President ordinarily does business: the bureaucrats, interest group leaders, journalists, Congressmen, and party leaders of official Washington … To most of these groups in the course of his Presidency Nixon gave intentional offense, and in each case it was offense of a character that carried with it a clear threat of a very basic kind … Nixon's policies … consisted of a systematic trampling of his political fences, a direct assertion that the legitimacy of the Presidency entailed the illegitimacy of those other political elites to whom a President normally is accountable.

Every president since at least Woodrow Wilson has shown some inclination to believe that the election conferred almost mystical connections between the president and the nation. And Trump, to be sure, hasn’t seemed to need the (sort-of) validation of the electorate to feel that he alone is the voice of authority on pretty much every topic and that no one else has any legitimacy whatsoever. Nixon took this to an extreme. 

Now Trump appears determined to follow more intently in his footsteps. It’s normal for presidents to fight back against congressional oversight; it’s not normal for the president to declare that “we’re fighting all the subpoenas.” On what grounds? Trump says it’s because “These aren’t, like, impartial people.” This is simply an argument that Congress as a whole is an illegitimate part of the government, given that Congress is never “impartial” and was never intended to be. 

Greg Sargent in the Washington Post has made the interesting argument that Trump, by also arguing in part that he doesn’t have to comply with congressional subpoenas not directly related to legislation, makes impeachment more likely given that impeachment and removal (and investigations to support it) are obviously a part of Congress’s business. 

But I think it goes a lot further than that. By insisting he is above the law – by insisting that the presidency cannot be checked by the other branches of government – Trump is forcing everyone else in the system to either accept a permanent shift in the constitutional order in favor of presidents, or to stand up and fight back. 

For the House, that makes impeachment a much more serious consideration. It also means that Congress should carefully consider the weapons available for fighting back other than impeachment, including aggressive use of the spending power, whether it’s to micromanage appropriations so the executive branch doesn’t have its usual discretion, or even to retaliate by cutting off funding for salaries to specific officials or to the White House generally. 

For Republicans in Congress, and for judges and justices who might otherwise tend to take a Republican president’s side, it forces the question: If push comes to shove, will they be loyal to their institution and the constitutional order, or to their party? Or, perhaps more accurately, to their party’s president.

In this polarized era, it’s not unusual for people from both parties to put partisan advantage over preserving the interests of their institution. For Republicans, however, it appears that Trump may put the question of party or institution to the test. Whether they say it out loud – whether they act on it – at least some of them have surely realized that if they side with him in crushing Congress as an institution, they won’t be in much of a position to fight back if Trump ever turns on them.

We’ve already seen several Senate Republicans stand up to him in the impoundment-like effort to get around congressional spending decisions by declaring an emergency over his border wall. We also know, from the Mueller report, that Republican senators successfully got the message across that firing special counsel Robert Mueller would produce an intense reaction from Congress.(2) We may soon find out whether they’re willing to defy him over Congress’s basic oversight responsibilities. If they don’t, they may find they no longer have those responsibilities, including when Democrats are in the White House.

And Vice President Mike Pence is still sitting right there, ready and able to be a normal Republican president if and when congressional Republicans decide they’ve had enough of the freak show.

(1) Even though Senate majority leader Mitch McConnell blocked votes on measures to actively protect Mueller, he and other Republicans made it clear that firing the special counsel was unacceptable. Andwhen Trump moved to do it, those around him argued that (the Republican-majority) Congress would be furious if they did what he asked.

To contact the author of this story: Jonathan Bernstein at jbernstein62@bloomberg.net

To contact the editor responsible for this story: Katy Roberts at kroberts29@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Jonathan Bernstein is a Bloomberg Opinion columnist covering politics and policy. He taught political science at the University of Texas at San Antonio and DePauw University and wrote A Plain Blog About Politics.

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