Immigration is one of the key issues in the November election, with many voters concerned over the numbers of migrants who have entered the U.S. during the Biden administration.
Republicans have repeatedly hammered President Joe Biden and Vice President Kamala Harris on the issue and painted a picture of an out-of-control immigration system where migrants are straining services as would-be terrorists and criminals take advantage of the chaos to infiltrate the country.
After coming into office promising a kinder approach to immigration, Biden administration officials found themselves struggling to control the southern border. They have cracked down on asylum access but also created new ways for migrants to come to America and for some of those already here to become citizens.
The administration has pointed to the falling numbers of migrants coming to the border this summer as proof its policies are working.
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Here's a look at where Harris and Trump stand on immigration:
Harris focuses on border security
During her first trip to the border as the Democratic presidential nominee on Friday, Harris outlined a plan to crack down further on asylum claims and extend restrictions put in place earlier this summer by the Biden administration on asylum access.
Before this trip, Harris has largely shied away from the topic of immigration and has given few details about what she would do if elected. That's a reflection of how the issue has become such a controversial topic for the Biden administration.
While Biden promised during the 2020 campaign to restore America's place as a refuge for people fleeing persecution, the administration swiftly found itself dealing with ever-increasing numbers of migrants at the southern border. Democratic-led cities rebelled at the strain migrants were taking on their cities.
The administration shifted to a more carrot-and-stick approach that made it harder for people who come to the border to get asylum while also creating new pathways designed to make the process more orderly.
In public comments and on her website, Harris has focused on ways she would enforce border security and crack down on drug smuggling.
The vice president has talked up her experience as California attorney general, saying she walked drug smuggler tunnels and successfully prosecuted gangs that moved narcotics and people across the border.
Early in his term, Biden made Harris his administration’s point person on the root causes of migration. Republicans have described it as a “border czar" position responsible for all border security, but her job was specific — figuring out long-term ways to stem migration from three countries in Central America. During a trip to Guatemala, she warned migrants thinking of coming to America: “Do not come.”
Harris has said Trump worsened the situation at the border by killing a bipartisan Senate compromise earlier this year that would have included toughening asylum standards and hiring more border agents, immigration judges and asylum officers. She said she would bring back that bill and sign it into law.
After hitting a record high in December 2023, the numbers of migrants crossing the border has plummeted since then. Harris and the administration have credited their tough anti-asylum measures for stemming the flow, although increased enforcement on the Mexican side has also played a key role.
The vice president has endorsed comprehensive immigration reform, seeking pathways to citizenship for immigrants in the U.S. without legal status, with a faster track for people living in the country illegally who arrived as children.
She hasn't weighed in on whether she would continue key Biden administration programs that have allowed more than a million migrants to enter the country — the carrot of the carrot-and-stick approach.
Migrants can use an app called CBP One to schedule an appointment while they're in Mexico to present themselves at an official border crossing for entry. Also, 30,000 migrants a month from Cuba, Haiti, Nicaragua and Venezuela can come to America for two years and get a work permit, assuming they have a financial sponsor, pass vetting and fly into an American airport.
Harris also has lashed out at Trump’s zero-tolerance policies that separated families at the border to try to deter immigration.
Trump vows mass deportations
Immigration was the issue that propelled Trump into the White House the first time and what he hopes will give him another term.
During just about every campaign speech or appearance, he has portrayed immigration as out of control.
One of Trump's key promises if reelected is to mount the largest domestic deportation in U.S. history. He made similar promises when he first ran for office, but during his administration, deportations never topped 350,000.
For comparison, then-President Barack Obama carried out 432,000 deportations in 2013, the highest annual total since records were kept.
This time, Trump has given some more specifics on his promises. He said he'll use the National Guard to round up migrants. And he said he would invoke the Alien Enemies Act, a 1798 law that allows the president to deport any noncitizen from a country that the U.S. is at war with.
He's also vowed to kick out hundreds of thousands of immigrants who have entered the country under two key Biden administration programs if he’s reelected.
Any mass deportation plans would certainly be challenged in court and be enormously expensive to carry out. And it would depend on countries being willing to take back their citizens.
Trump says he also would bring back policies he put in place during his first term, like the Remain in Mexico program and Title 42. Remain in Mexico made migrants wait in Mexico while their asylum cases were heard, while Title 42 curbed immigration on public health grounds.
He has said he'll revive and expand a travel ban from his term that originally targeted citizens from seven Muslim-majority countries and pledged new “ideological screening” for immigrants to bar “dangerous lunatics, haters, bigots and maniacs.”
Trump also seeks to end birthright citizenship for people born in the U.S. whose parents are both in the country illegally.