Perhaps the best argument against the re-election of President Trump in 2020 will be that his first term has been so exhausting. There have not been times of relative peace under his administration. There are only crises, one begetting another, until they all melt together into a blob of constant, unending emergency.

It's too much.

In a better world, the end of Special Counsel Robert Mueller's investigation might have provided both Trump and Americans a respite from scandal that has been nipping at the president's heels since before he took office. Instead, that controversy continues, with new ones being added to the pile all the time. Last week, it was the failure of Attorney General William Barr to respond to a House committee subpoena. This week, Treasury Secretary Steven Mnuchin refused to hand over the president's tax records to Democrats running the House Ways and Means Committee.

"I have determined that the committee's request lacks a legitimate legislative purpose," Mnuchin wrote in a letter announcing his decision.

Let's be fair to both Mnuchin and the president for a moment: It actually is kind of alarming that Congress is empowered to dig into the tax records of any private American it so chooses. If Republicans had used the law to dig up President Obama's financial history, Democrats would have complained loudly and strenuously.

Then again, Republicans didn't have to do that, because Obama — like other presidents and presidential candidates since Richard Nixon — released his tax returns to the public. Trump has made himself the first exception to that norm in more than 40 years, offering a series of lousy excuses along the way. Given all the ways Trump's presidency might be compromised by his financial interests, it's fair for Americans to expect more transparency and accountability.

What's more, as has been widely noted, Congress' power to demand those tax records has been part of the law for nearly a century. The law doesn't give Mnuchin or any other executive branch individual the authority to evaluate the legitimacy of congressional intent in obtaining the records — it says only that the secretary "shall" give them to Congress upon written request from the chair of either congressional tax committee.

By almost all accounts, the law is unambiguous. Trump and Mnuchin are defying it anyway, which means Congress has yet another fight with the president on its hands.

One could argue that this state of perpetual crisis isn't entirely Trump's fault. The president never got any kind of honeymoon with the public; Democrats declared their opposition and started their investigations almost immediately. While Trump has offered them ample reason to inquire, it's also true that they have political motivations for doing so. In the post-Benghazi world, it may ever be thus for every future president.

But Trump and his advisers seem to go out of the way — intentionally or not — to add to the pile of emergencies. Just this week, Trump suddenly threatened to hit China with a new round of tariffs, despite recent indications that the two sides were close to finalizing a trade deal. Secretary of State Mike Pompeo publicly entertained the thought of sending U.S. troops to Venezuela — and wouldn't commit to consulting with Congress on the matter, even though the Constitution gives war-making powers to the legislative branch. Trump's national security adviser, John Bolton, announced that an aircraft carrier was being deployed to the Persian Gulf to defend against unidentified provocations from Iran. It seems showdowns loom on every front.

Lurking in the background is the lawsuit against Trump over his possible violations of the emoluments clause, the devastation being done to the American farm sector as the result of the president's trade wars, and the growing nightmares created by his immigration policy.

Is the perpetual drama a product of design, or does it simply reflect Trump's own taste for chaos? It may not matter. There is plenty of evidence to suggest that Trump enjoys constant drama. That his presidency is a constant parade of confrontations and cliffhangers should come as no surprise.

One thing we do know is that humans, when confronted by unending stress, end up depressed, frazzled, and sick. It's fair to wonder if the same is true of the body politic. These times are not good for America. Mnuchin has triggered the latest crisis for the Trump administration, but it surely won't be the last. It might not even be the last this week.