For the chronically indebted businessman Donald Trump, it was a win every day the creditors did not foreclose on him.

President Trump will manage the remainder of his presidency the same way.

The appointment of Robert Mueller as special counsel in the Trump-Russia matter will spell vexation in the medium term and may spell danger in the long term. But in the here and now—the next days and weeks, easing into months—the appointment brings relief.

Republicans in Congress have gained a new excuse to revert to their prior enabling of Trump’s misconduct: A special counsel has been appointed!

Instead of defiantly lying, the White House staff can now refuse to answer questions outright: A special counsel has been appointed!

Fundamental questions of national security and public integrity will go unexplored as the special counsel focuses on narrow legal matters. The public debate will be starved of new information as the special counsel proceeds in legally required secrecy.

Yet we can already perceive some of the legal first consequences of the appointment.

The special counsel will investigate whether the president’s message to James Comey about Michael Flynn—“I hope you can let this go”—followed by Comey’s firing, meet the test of prosecutable obstruction of justice. (Expect hundreds of hours of cable-TV airtime for anyone with plausible-sounding legal credentials willing to argue the contrary side of the case.)

Meanwhile, what happened in plain sight—the president fired an FBI director for doing his job—will dwindle into secondary importance.

The special counsel will investigate whether people in the Trump campaign violated any laws when they gleefully leveraged the fruits of Russian espionage to advance their campaign.

By contrast, what happened in plain sight—cheering rather than condemning a Russian attack on American democracy—will be treated as a non-issue, because it was not criminal, merely anti-democratic and disloyal.

If it can be proved that Flynn intentionally altered U.S. foreign policy in Turkey’s favor in knowing return for money, he will face legal jeopardy.

But if the motives cannot be proved beyond a reasonable doubt, the story will disappear from the inquiry.  

If the special counsel chooses, he may write a report providing larger context for the troubling events. The Trump Justice Department will then decide whether to release that report to the public.

The counsel’s mandate, however, only empowers him to investigate connections between Russia and the Trump campaign. It’s by no means clear that he has authority to broaden the inquiry into the mighty question of why Russia chose to intervene, or to explore entanglements between the Russian government and Trump’s businesses.

People in Trump’s orbit now face legal fees and legal jeopardy. For a long time however, the president himself will enjoy the shield of Robert Mueller’s professional discretion.

It doesn’t have to be this way. Congress could still investigate itself or empower an independent investigation. This Congress won’t. The next Congress should.

Perhaps it should start on exactly the terrain put off limits to Mueller: The pre-2015 history of connections between Trump and Russia. Congress has power to subpoena the business records of the Trump Organization. It can trace the complex system of holding companies within which (according to Trump biographer Timothy O’Brien) Trump hides his enormous debts. It can order a forensic audit to clarify exactly what the Trump family has received from Russian sources over the years, and what it may still owe.

Very likely none of this is illegal. It is, however, burningly relevant.

This generation’s variant of “What did the president know, and when he know it?” Is “What does the president owe, and to whom does he owe it?”

Not: “Is the president a crook?” (We had available all the information needed to determine that on election day.)

But: “Is the president a risk to national security?”

The most urgent task ahead is not a criminal investigation, potentially leading to indictments and prosecution.

The most urgent task ahead is a broader counter-espionage inquiry conducted not to mete out punishments, but to discover and publicize the truth, however disturbing.