When President Barack Obama took executive action to provide reasonable protections for immigrants, including Dreamers, an outspoken critic tweeted a message to Republicans in Congress.

“Repubs must not allow Pres Obama to subvert the Constitution of the US for his own benefit & because he is unable to negotiate w/ Congress,” wrote Donald J. Trump on November 20, 2014.

Around the same time, another outspoken critic outlined reasons for opposing Obama’s order.

“I think it would be a profound mistake for the President of the United States to overturn American immigration law with the stroke of a pen,” Indiana Governor Mike Pence told a Republican Governors Association conference. Imploring the president to respect the role of the Congress, Pence declared that “Issues of this magnitude should always be resolved with the consent of the governed.”

Now, consider what Obama actually did. The American Immigration Council noted at the time that, after “acknowledging the failure to reach a legislative solution that addresses the fate of unauthorized immigrants who have lived in the country for years” the 44th president “authorized the Department of Homeland Security to significantly expand its use of deferred action to provide temporary protection from removal for millions of unauthorized immigrants currently in the U.S.” That was a reasonably bold move, but not an entirely unprecedented act. “Since 1956, every U.S. president since Eisenhower has taken executive action to grant temporary immigration relief to those in need of assistance,” the council explained in 2014. “In at least 39 instances, presidents have acted to protect families from separation, in response to foreign policy crises, or in recognition of pending legislation.”

So it is fair to say that Trump and Pence went overboard in their criticism of Obama.

But for those who choose to give Trump and Pence the benefit of the doubt, and who presume that they were sincere in their pronouncements, then it is also fair to say that the standards Trump and Pence established as a private citizen and a governor in 2014 are relevant to what Trump just did as president.

On Friday, Trump declared a national emergency that he plans to exploit to divert money to a pet project that he popularized with his political base and that he is now under pressure to implement. For purposes of building a border wall that is neither warranted nor practical, the president and his aides and enablers (including now Vice President Mike Pence) are upending the clear intent of the Constitution, which affords to Congress the power of the purse.

House Speaker Nancy Pelosi and Senate minority leader Chuck Schumer argued that “declaring a national emergency would be a lawless act, a gross abuse of the power of the presidency and a desperate attempt to distract from the fact that President Trump broke his core promise to have Mexico pay for his wall.”

The Democratic leaders are correct on all three counts. And at least some of their concerns have been echoed by Republicans such as Utah Congressman Chris Stewart, who said Thursday, “I think President Trump is making a mistake by declaring a national emergency in order to increase border funding. Whether the President has the authority or not, it sets a dangerous precedent and places America on a path that we will regret.”

So this is a serious matter that has raised bipartisan concern.

Trump, it would seem, has become what he fretted about in his most overheated statements of five years ago: a president who subverts the Constitution “for his own benefit & because he is unable to negotiate w/ Congress.” He has made the “terrible mistake” that Pence imagined when he complained about an administration’s rejecting the consent of the governed on an issue of magnitude.

So how should Congress respond?

Legal challenges are expected. “Many Democrats predict their chamber would quickly pass a resolution instructing the House counsel to sue the administration for ignoring the appropriations clause in the Constitution,” reports Politico. “Congress, after all, has the power of the purse. And Democrats would likely have standing to challenge the administration for usurping their authority for what they view as a phony emergency.” California Attorney General Xavier Becerra argues that “The idea of declaring a state of emergency on the border that does not exist, to justify robbing funds that belong to the victims of fires, floods and hurricanes, to pay for the wall is not only immoral, it is illegal.”

The courts may deal blows to Trump’s national-emergency order, just as they dealt blows to Obama’s orders. Yet members of Congress need not wait for the courts to trump Trump.

The National Emergencies Act includes a clause that permits Congress to terminate an emergency that is declared by a president. The House can and should vote to do this. It will be harder in the Republican-controlled Senate, but effort should be made there, as well—even if the president issues a veto threat.

Key committee chairs can use their oversight authority and the budget process to try to place restrictions on the funds that the president might divert. But is there more that members of the House can do right now? Let’s turn to Trump. In 2014, he used an appearance on Fox News to argue that a president who could not make a deal on immigration policy and then used executive action to get around Congress “certainly did something that’s unconstitutional.”

Such a president, Trump said, “certainly could be impeached.”