Democratic New York Mayor Bill de Blasio, who reportedly may run for president, once told the truth about one of the many problems with illegal immigration. If he’s confronted with it in his party’s presidential primary, he’ll almost certainly apologize.

The Democratic Party's line on immigration is simple: Maintain that everyone should be allowed in, and deny that there’s ever a single reason they shouldn’t be.

There might be some rapists? Racist!

There might be some child molesters? How dare you!

There might be some drug smugglers or even violent gang members? “We are all God’s children.”

OK, but what about the potential spread of disease by foreigners who come from countries with substandard healthcare? De Blasio is at least on record admitting that, yes, that does happen.

“The officials here also told us that these kids come with physical challenges, because they were held in detention, they come with the evidence of that,” said last June after touring a detention facility in his city. “They've said that a number of kids have come with lice, have come with bedbugs, have come with chickenpox, physical diseases, and contagious situations that just make it worse for everyone else.”

His overall point was that the detention centers make the spread of disease more rapid. That's probably true as well, but then the alternative is to turn contagion-ridden migrants loose on the rest of the population.

It takes no guesswork to figure out the Democratic position on this. It’s all on the record.

Former Department of Housing and Urban Development Secretary Julian Castro, another Democrat running for the nomination, wants to decriminalize unauthorized border crossing, in effect rendering the term “illegal immigrant” obsolete altogether.

Beto O’Rourke, another 2020 Democrat, is not only opposed to building more border barrier, but he wants to tear down the existing structures.

California Sen. Kamala Harris, another 2020 candidate, sees similarities between the way Immigration and Customs Enforcement agents operate and the Ku Klux Klan.

South Bend, Ind., Mayor Pete Buttigieg, who believes in God and is also a 2020 Democrat, said he would welcome any and every immigrant to his city, repeating the lie that they aren’t able to consume welfare benefits and, in fact, are merely “subsidizing the rest of us.”

Rep. Alexandria Ocasio-Cortez, D-N.Y., the new unofficial leader of the House Democratic caucus, says that ICE should be abolished altogether.

Rep. Xochitl Torres Small, D-N.M., said in an interview last year on CNN that the priority on immigration enforcement should be “medical equipment, as well as personnel, [and] appropriate facilities” to detain families so that they all remain “safe and healthy.”

De Blasio once told the truth about immigration. Before he runs for the presidential nomination, he should know that the truth is not allowed on his party's national level anymore.