Is US in constitutional crisis? That may not be most important question.

President Donald Trump’s pledge of non-cooperation with the impeachment inquiry of the Democratic-controlled House of Representatives may or may not be a “constitutional crisis.” But it is a stark new test of the nation’s founding legal document – perhaps the most important such trial since Richard Nixon declined to turn over the White House tapes. How it’s resolved could reset the balance of power between the executive and legislative branches of government in our polarized political age.

This test is only partly a legal matter. It’s also political – an appeal for the support of the “jury” of American voters. President Trump’s combative letter to the House on Tuesday seemed as much directed toward his rally-going base as a serious attempt to argue legal issues with Democratic leaders. If he maintains his popularity among GOP voters, it’s highly unlikely the impeachment process will result in his removal from office.

“Trump has never been the type of president who has tried to appear above the fray, ever. You can make the argument that part of what’s made him successful with Republicans is his willingness to be competitive,” says James Curry, a political science professor at the University of Utah.

Experts who believe the country is in a constitutional crisis argue that the current standoff between Mr. Trump and the House isn’t something the Constitution per se will be able to resolve.

The dispute stems from the fact the president is refusing to provide documents or witness testimony subpoenaed by the House. In his fiery letter to Speaker Nancy Pelosi this week, White House counsel Pat Cipollone argued that the House impeachment inquiry was “illegitimate,” in part because the House had not authorized it with a full vote, presidential attorneys would not be able to question witnesses, and other irregularities.

But House subpoena power is well-established in law. And the Constitution gives the House the power to impeach, and says nothing else on the subject – allowing House leadership to conduct impeachment inquiries under whatever procedures and inquiries they choose.

It’s true they have yet to hold a full vote authorizing an impeachment inquiry, as was conducted prior to investigations of Presidents Nixon and Bill Clinton. But nothing in the law requires them to do so.

Meanwhile, the House is struggling to enforce its constitutional prerogatives. Civil suits intended to force compliance with past subpoenas are wending their way – slowly – through the courts. Any legal action dealing with impeachment subpoenas might not be completed until after the 2020 election. 

The Founding Fathers gave Congress what they felt was a powerful means to prevail in a competition between the branches of government – the ability of the House to impeach presidents and the Senate to vote to remove them. But they did not envision a U.S. where the political fault lines would be party versus party, not legislative versus executive. The result: the current mess of inaction and conflicting claims.

“To me the right term is constitutional failure,” says Chris Edelson, an assistant professor of government in the School of Public Affairs at American University. “The reason I say that is because the system is not working in the way it was intended and designed to work. It was designed as a system of checks and balances, where when one branch goes too far, another reins it in.”

The Constitution is not self-executing, adds William Galston, a senior fellow in governance at the Brookings Institution in Washington. Its effectiveness depends on men and women being willing to defend the governmental institutions they belong to, including Congress.

“We’re in a situation now unfortunately where hyperpartisanship leads a lot of people who should be defending Congress to defend the president instead, whatever he does. And this is a real problem for our constitutional order,” Dr. Galston says.

Realistically, the ultimate answer to the current standoff is voting. The American people will have to choose and resolve the issues involved at the ballot box, he says. “I don’t think constitutional mechanisms are enough,” Dr. Galston says.

In the end the nomenclature may not be the most important thing. Calling today’s situation in the U.S. a constitutional “crisis,” or “stress test,” or “normal struggle,” does not tell us anything we don’t already know.

“Nothing as a practical matter changes if we say it is, or is not, a ‘crisis,’” says Marty Lederman, a law professor at Georgetown University Law Center, in an email.

Much will depend on whether Mr. Trump remains adamant about not cooperating with any House subpoena – particularly if courts rule against him.

That could produce something most everyone would recognize as a crisis point.

One possible, maybe even probable, course of action could run like this: The White House is really just trying to slow down the process to lessen its political bite. Meanwhile, Mr. Trump is engaging in his usual bluster. He’ll lose in the courts, and maybe even provide an obstruction count for impeachment in the House.

But at this point, it seems very likely that the president will be impeached. Perhaps he recognizes this. Obstructing the inquiry as he is could help him with the GOP base. And maintaining their support is the key.

“As long as the base stays with him, there will not be 17 GOP senators who will vote to remove – meaning he will survive,” writes David Barker, director of the Center for Congressional and Presidential Studies at American University, in an email.