What did Donald Trump do today?

He basically admitted that he thought judges obeyed the president who appointed them.

This morning, U.S. District judge Amit Mehta, who was appointed by President Obama, issued a strongly worded but totally expected ruling denying Trump's attempt to block one of his accounting firms from responding to a Congressional subpoena. Trump, who for one reason or another is desperate to avoid any scrutiny of his finances, had been forced to claim that Congress had essentially no oversight role where the presidency was concerned. Mehta cited Congressional investigations into presidents from James Buchanan to Barack Obama in a 41-page decision, and concluded:

It is simply not fathomable that a Constitution that grants Congress the power to remove a President for reasons including criminal behavior would deny Congress the power to investigate him for unlawful conduct—past or present—even without formally opening an impeachment inquiry. ...This court is not prepared to roll back the tide of history.

Trump responded by suggesting that the "crazy" legal opinion of "obviously, an Obama-appointed judge" didn't matter. This is part of Trump's traditional view of government, that he is personally owed "loyalty" from people he's given appointments or government jobs to—and where legal matters are concerned, personal protection.

Also today, Trump issued a last-minute order demanding that his former White House counsel Don McGahn not testify before the House Judiciary Committee tomorrow. (McGahn has been the target of Trump's outrage for several weeks now, after the Mueller report portrayed him as defying Trump in order to save Trump from committing prosecutable acts of obstruction.)

Trump, who continues to insist that he has been "totally transparent," is also currently fighting subpoenas to release his tax returns to Congress, suing Deutsche Bank (to whom he owes at least $130 million) to prevent them from cooperating with an investigation into his finances, declaring the entire Mueller report to be subject to executive privilege, and insisting that he will appeal any attempt at impeachment to the Supreme Court. (It doesn't work that way, although Trump may honestly believe that he can force justices he appointed to rule in his favor if he can somehow get it there.)

Why is this a problem?

• The president is not above the law.

• In American democracy under the Constitution, the presidency is subject to oversight by Congress and rulings by the judiciary.

• People with nothing to hide don't spend this much time and effort trying to hide things.