Confronting the fraught politics of immigration, President Biden wants to focus attention on the decision by Republicans in Congress, egged on by former President Donald J. Trump, to block a bipartisan deal that would provide an infusion of money for border security and allow the president to close off the border to asylum seekers.
On the defensive, Republicans have escalated their longstanding effort to tie migrants to heinous crimes.
Both strategies were on full display on Thursday night as Mr. Biden delivered his State of the Union address. He made his case that it is Republicans who are now responsible for the problems at the border, while Republicans portrayed his policies as responsible for the death of Laken Riley, a 22-year-old nursing student from Georgia who was killed in February, allegedly by a Venezuelan migrant.
The dynamic has Mr. Biden, who heading into the general election campaign has signaled a harder line on immigration, walking a careful line, as his clash with Republicans on Thursday night demonstrated. He at once promised to bring back “order” at the border while also vowing not to assail migrants in the manner of Mr. Trump and his allies.
“I will not demonize immigrants saying they are poison in the blood of our country,” Mr. Biden said in his address before a joint session of Congress, referring to statements by Mr. Trump that have echoes of white supremacy.
“Unlike my predecessor, I know who we are as Americans, and we’re the only nation in the world with the heart and soul that draws from old and new,” Mr. Biden said. “Home to Native Americans whose ancestors have been here for thousands of years, home to people from every place on Earth.”
When heckled by Representative Marjorie Taylor Greene, Republican of Georgia, about Ms. Riley’s killing, he interrupted his prepared text to respond.
“An innocent young woman who was killed by an illegal. That’s right,” Mr. Biden said to Ms. Greene, using a term criticized as dehumanizing by many Democrats.
But he then asserted that there were thousands of murders committed by what he called “legals,” people who legally reside in the United States.
While there has long been a concerted focus to connect immigrants to increases in crime, Charis E. Kubrin, a professor of criminology, law and society at the University of California, Irvine, said that the emphasis was misguided.
“What we’ve found is that increases in immigration to areas either have no impact on crime or cause crime to go down on average,” she said about her research, adding that the Riley case offered an opportunity to “politicize this issue which is already political.”
Nonetheless, the intersection of immigration and crime has long spoken to fears of a threat from outsiders with ill intentions.
Mr. Trump, who has called immigrants killers, rapists and drug peddlers, often focused on the killing of Kate Steinle in San Francisco in 2015 and the subsequent arrest of an undocumented man in the case. He connected border policies to the crime in discussing the case.
“Donald Trump was able to capture the agenda and the headlines of immigrant criminality by repeatedly mentioning Steinle in his speeches without a great response from people running against him, including Hillary Clinton at that time,” said P. Deep Gulasekaram, a professor of immigration law at the University of Colorado Law School. “It has a lot of salience. It had it in 2015 and 2016, and it clearly has salience again.”
But the issue does not always play out predictably.
In July 2018, Mollie Tibbetts, a 20-year-old college student in Iowa, was murdered by an undocumented man. The case drew national attention, and Mr. Trump called on immigration laws to be changed.
In an opinion essay published in The Des Moines Register, her father called on people to not politicize the killing.
“The person who is accused of taking Mollie’s life is no more a reflection of the Hispanic community as white supremacists are of all white people,” he wrote. “To suggest otherwise is a lie. Justice in my America is blind.”
Tom Jawetz, a former official at the Homeland Security Department under Mr. Biden, said that it appeared that the president was trying to accomplish three things: to condemn Ms. Riley’s killing as a tragedy; to sympathize with her parents and to call out Republicans for connecting immigrants to criminality.
Mr. Jawetz said it was notable that Mr. Biden, in an oblique manner, was “making the point that thousands are killed by American citizens and are not demagogued.”
Mr. Jawetz said Mr. Biden would need to be prepared for the topic to come up again and to sharpen his message. The president’s reference to the suspect in the case as “an illegal” has already drawn significant blowback from immigrant advocates.
The politics of immigration show no signs of becoming less intense even as Mr. Biden, under election-year pressure, has shifted to the right. On Thursday, the House passed legislation named for Ms. Riley.
The measure, which would require that migrant who enter the country illegally be detained if they are accused of theft, has little chance of moving forward in the Democratic-led Senate, but Republicans used it to force Democrats into an uncomfortable vote.
The gambit appears to have worked to a degree — 37 House Democrats backed the legislation, which denounced the “open borders” policies of the Biden administration.
Andrea Flores, a former Biden administration official, said that the president’s ad-lib response to Republicans during his State of the Union address was similar to his working with Republicans on a border deal.
“He can be responsive to their rhetoric but at the end of the day, he’s the only one who can start changing conditions on the ground,” she said, noting that action in Congress was especially unlikely. “It is of limited value to utilize these arguments that maybe Democrats have avoided until the administration can show voters that they have a better plan,” she said.