Unlimited illegal immigration—that’s what a Biden administration wants, and that is what it will be able to get after Jan. 20.

This is perhaps the most important domestic policy issue at stake for America as we face single-party leadership in both chambers of Congress and the White House. And it couldn’t come at a worse time for our country as Americans struggle to keep businesses open and regain a public health footing from the ongoing effects of the COVID-19 virus.

President-elect Joe Biden has a long record of calling for unlimited immigration.

In 2015, he was recalling a conversation he had with a former president of Singapore about what separates America. He stated that it was “an unrelenting stream of immigration—nonstop, nonstop.”

He had previously expressed this desire to the National Association of Manufacturers, where he said that the “constant, unrelenting stream” of immigrants into the U.S. was the basis for our economic strength.

He emphasized that he wanted “not dribbling” amounts, but “significant flows.”

With the left in control of the U.S. Senate, the Biden administration has a Congress available to rubber-stamp its most radical immigration agenda items. And make no mistake: The left will not waste this political opportunity. Its leaders understand that mass immigration historically transfers into more leftist voters.

It’s no coincidence that the open-borders lobby has found a permanent home with leftists. It means pure political power. Look no further than California as Exhibit A.

So, what can the Biden administration do with a House and Senate controlled by the far left? First, it can seek to legalize all illegal aliens within the U.S., with token exceptions for some hardened criminals.

Keep in mind that the U.S. doesn’t even know how many illegal aliens are here, in part because the left has opposed any effort to try to better understand that number. The Biden team claims it is around 11 million, but other estimates top 22 million.

Such an amnesty effort would not make any attempt at assimilating illegal aliens into the U.S. mainstream—adopting our language, culture, and patriotism.

Second, the borders would be open and overrun. Promising amnesty has already resulted in a run on the border, or the “Biden Effect.” Once the wheels start moving toward the largest amnesty in our history, the Border Patrol would be overwhelmed by illegal aliens seeking to get their claim to the most prized passport in the world—and all the government benefits that come along with it.

Couple this green light with stand-down orders to the Border Patrol and Immigration and Customs Enforcement, and you have a recipe for absolute disaster without any limiting principle. A recent Gallup poll found that more than 158 million adults would migrate to the United States if they could.

With a Biden presidency and a leftist-controlled Congress, what will be able to stop them?

Third, scarce resources would be directed away from current Americans and toward amnestied immigrants. This means it would be open season on the buffet of federal government welfare programs, as well as the continued strain on America’s job availability, education budgets, health care costs, and public safety resources.

Translation? Americans forced to compete for employment opportunities as wages decrease, crowded schools with burgeoning numbers of students who don’t speak English, rising health care costs, increased COVID-19 spread, and more gang-related crime, as Americans have seen from the ruthless MS-13 where it has taken hold.

But as Biden says of illegal immigrants, “We owe them.”

Americans are directly affected by immigration policy in many important aspects of our lives—jobs, the economy, education, health care, crime, and national security.

Americans and lawful immigrants want our immigration laws enforced and our borders secured.

Yet, we are on the verge of having neither. With the White House and Congress under single-party leadership, it will be up to the American people to frequently and loudly voice their opinion that open borders and amnesty are wrong for America.

This column first appeared in The Washington Times.