President Donald Trump speaks to reporters during a news conference...

President Donald Trump speaks to reporters during a news conference in the Brady Press Briefing Room at the White House on Tuesday. Credit: Getty Images/Chip Somodevilla

It should come as no surprise that President Donald Trump is making another run at politicizing the U.S. Census. He has repeatedly and wrongly tried to limit who is included in the decennial head count. Having been stymied by the federal courts, he now is attempting to effectively remove them from the mandate for an "actual Enumeration" of all people in the country after the count is completed.

It wasn't right then, and it isn't right now. With November's election looming, Trump is flagging in the polls against former Vice President Joe Biden and has been looking for fuel to feed his anti-immigrant base. That just makes his latest action all the more cynical. 

The Constitution's mandate to count all people every 10 years is primarily to determine how many members of the House of Representatives each state will have. The census count also determines how many federal dollars flow to each state and it also provides essential data for many other programs. The president signed a memorandum Tuesday that would exclude immigrants in the country illegally from that calculation.

Trump's memorandum is so patently wrong, it's unlikely to survive a court challenge. But as with other red-meat challenges, it's not whether the rule is ever put in place in the long run,  it's how it plays politically in the short term.

Trump's latest constitutional assault comes a year after the Supreme Court blocked his attempt to add a citizenship question to the census, a move that was exposed as an effort to stop immigrants here illegally from filling out the census for fear that revealing their status would lead to deportation.

Depressing those numbers would hurt states and regions with large numbers of such immigrants, such as New York City and Long Island, since the census also is used in population-dependent formulas for funding for health care, housing and education. Since states are obligated by law to provide many services for all residents, regardless of citizenship status, an accurate count of all residents is essential. Academic researchers and former and current census officials said a citizenship question might have produced an undercount of as many as 6.5 million people; Trump's new attempt to exclude them after the count could achieve a similar undercount.

Besides being unconstitutional, the president's gambit also is unworkable. How is the administration going to determine accurately who in the census is in the country illegally? And it might not have the effect he intends; it also would hurt red states with sizable immigrant populations working, for example, in meatpacking plants or on industrial farms or living along the Southern border. 

After signing the memorandum, Trump issued a statement that said there "used to be a time when you could proudly declare, 'I am a citizen of the United States.'" You still can. But part of that proud declaration is that you also are proud to abide by the Constitution. That's true for everyone, the president included.

— The editorial board