There are several clues that Donald Trump is taking the possibility of his criminal prosecution seriously. First of all, he’s calling the investigations “witch hunts,” which is what he always does when he’s guilty as sin. “Which witch hunt?” those of you who have managed to put Trump out of your mind might ask.

You and the fam might be deep in planning a summer vacation -- perhaps a ballgame. The spotlight on COVID and that other disease, the deadly Trump blight, has faded.

Still, it could flare up again. Right now, he’s not rattling around the White House, so the walls protecting him from prosecution have come tumbling down. As a result, now Trump can face legal jeopardy, the serious criminal kind that potentially carries with it incarceration. A step closer, and the investigations cannot be deflected as “fake news.”

The two main issues have focused on business practices of the Trump Organization that were simmering beneath the surface mainly as a civil matter. Now they have seeped into reality with a criminal grand jury and all its awesome subpoena power.

And the Don is squirming. He blasted in a statement: “There is nothing more corrupt than an investigation that is in desperate search of a crime.”

The crimes that prosecutors may be exploring are the fraud type. The Trump Organization may have intentionally cooked the books when describing the value of its assets, but poormouthed those same assets when listing them for tax purposes. That’s a serious violation, fraud, and while the company had many individuals who could theoretically make those types of big decisions, few of them were carried out without Trump personally signing off on them.

But it’s a long way from here to there, “there” being an indictment of Donald Trump, 45th president of the United States. And a huge problem for the 46th, Joe Biden.

Suppose Trump is officially accused of criminal actions. There is only so much Biden can do. These are state charges; they would be tried in state courts, which is not in Joe Biden’s direct chain of command. However, Biden could decide whether the feds get involved

by instructing his Department of Justice to begin a process of investigations.

Actually, it’s an open question of semantics, whether it’s “his” Department of Justice or whether it is responsible to “the people.” Tradition calls for a president to stay out of such DOJ matters, tradition that Trump, as president, routinely ignored. And Biden would have to decide whether he could get personally involved and credibly pull it off.

Whether he does or not, Biden could face the spectacle of a former chief executive standing trial in criminal court, something that has never happened before. Not only would that be a disgrace to Trump, it would disgrace the United States of America.

Furthermore, our leaders would loudly insist that they would not be intimidated by the violence of huge crowds of Donald Trump supporters, whipped into a frenzy by opportunistic white supremacists and other extremists. Yes, the feds could be intimidated, if nothing else than by the prospect of watching the collapse of our nation.

Remember, the mobs were the same revved up Americans, persuaded by Trump’s ridiculous lies that he had the election stolen from him. They were willing to shred the most sacred U.S. tradition, the vote, on the word of one man, a known liar. They invaded the U.S. Capitol building, and they could take over other buildings, possibly bringing the government to its knees. Not only would the country not be “exceptional,” it might be rubble, with a deranged authoritarian bent on revenge taking charge, the same one who was previously charged with violating the law.

It would be a test of democracy, a test that this country might fail. Given the cynicism that nearly everyone has about politics and politicians, America is weakened. We are a fragile country, so Donald Trump’s biggest crimes of all may be yet to come.

Bob Franken is an Emmy Award-winning reporter who covered Washington for more than 20 years with CNN.