CORRECTION Mexico Migrant Caravan

Central American migrants, part of a caravan hoping to reach the U.S. border, walk on the shoulder of a road in Frontera Hidalgo, Mexico, Friday, April 12, 2019.  (AP Photo/Isabel Mateos)

The flap over President Trump’s threat to bus migrants to so-called sanctuary cities if Congress does not act quickly to reform immigration law has generated a lively debate that is mostly beside the point.

The president is right that the crisis on the U.S.-Mexico border demands quick legislative action to fix a major problem with immigration amnesty. If not, the surge in migrants will continue. A bipartisan willingness to tackle this difficult subject should also open the door to comprehensive immigration reform, including such all-but-overlooked issues as the fate of the “Dreamers.”

Here’s the problem: If a migrant makes it to the southern border or crosses illegally and claims asylum, the government is obliged to provide an asylum hearing, a process that can take months to schedule because of clogged immigration courts.

The current overwhelming number of migrants at the border are mostly seeking asylum relying on the law and its liberal expansion by a generation of legal opinions. But detention facilities are overcrowded so many must be released. Some of them hide from law enforcement and skip their court date.

As long as the existing legal framework is allowed to remain on the books, the immigration system suffers from inadequate funding and the border remains easy to cross, people from trouble-plagued Central American countries will continue their perilous trek toward what they hope will be a better life.

Those who make it across the border will go where the culture is friendliest. The flows will be toward the cities that offer them protection from federal immigration enforcement by refusing to spend city funds to assist the federal government.

So whether or not President Trump provides the buses, many illegal immigrants will eventually find their way to sanctuary cities. The mayor of Burlington, Vt., says she will welcome illegal immigrants, even those bused in by President Trump, “with open arms.”

Sanctuary cities encourage illegal immigration, and are one of the many incentives for the current surge. They are defying national law, claiming higher ground.

They are also playing a numbers game. Many large federal benefits to states and local governments are apportioned by population, so the greater the influx of new people, the larger the fiscal benefit to the city. Congressional redistricting after the 2020 census will also be guided by where the people are, including noncitizens.

Nevertheless, many politicians who look with favor on sanctuary laws have denounced President Trump’s busing threat as dirty politics. House Speaker Nancy Pelosi, D-Calif., a resident of sanctuary city San Francisco, called the president’s taunt “unworthy.” Luke Bronin, mayor of sanctuary city Hartford, Conn., said the president was “weaponizing families seeking a better life.”

However, the reaction against Mr. Trump does more than suggest hypocrisy on the part of some proponents of open migration. It shows that even the sanctuaries rely on the current ineffective system to meter the inflow of illegal immigrants sufficiently that they do not become overwhelming burdens.

But the current system has broken down, and something must be done.

As Democratic presidential hopeful Sen. Bernie Sanders, I-Vt., recently said, “there’s a lot of poverty in this world” and we can’t afford to open the doors to everyone who wants to come here. Let us see if he offers to work with President Trump to lead the needed amnesty and immigration law reforms. Someone on the Democratic side needs to stand up at last on this issue.