Judges will determine specific executive limits

Give President Donald Trump credit for being transparent about his plan to exert executive authority in what many view as a challenge to Congress. At least Trump is not engaging in a covert operation.

For months, the president has insisted at least $5.7 billion is needed to erect new barriers against illegal immigration across the nation’s southern border. Last week, in a compromise intended to avoid another partial shutdown of federal agencies, Congress appropriated about $1.4 billion for the purpose.

Not enough, Trump declared. Friday, he told reporters at the White House he is declaring a national emergency over illegal immigration. He believes that gives him the authority to take money already appropriated for other initiatives and transfer it to the border barrier.

About $8 billion would be shifted out of other accounts to expand the existing line of border barriers.

At first glance, the obvious question may be why, if that much money is not needed for the purposes originally earmarked, was it in the federal budget in the first place? Eight billion dollars is far more than the total annual general fund budgets of eight states.

That is a question worth pondering, of course, but members of Congress never seem to ask.

Some, including a few Republicans, are asking whether Trump’s action is constitutional. That will be tested in the courts.

Trump is not the first president to divert federal funding. Former President Barack Obama did it by funneling billions of dollars into the Affordable Care Act. Some of it went to private insurance companies in subsidies intended to keep Obamacare insurance premiums artificially low. Obama did all that in secret, without even the pretext of a national emergency. So Trump should earn credit for openness.

What about constitutionality, however? Is he infringing upon Congress’ authority to appropriate money? Again, that will be decided by the courts.

Still, lawmakers are right to be concerned. Spending authority is a key facet of separation of powers. If Trump can declare an emergency on illegal immigration, what is to prevent a future president from doing so to fund some other pet project?

Except in a true national emergency, no president should be permitted to take money appropriated for one purpose and use it for another. Period. Whether this qualifies will be decided technically by judges and justices — but in a much larger sense, by the American people.