WASHINGTON -- In his address to the nation Sunday night, President Barack Obama will most likely urge Americans to "not give in to fear," detail measures the country is already taking to combat extremism and ask Congress to explore new ones, Attorney General Loretta Lynch said Sunday.
"What you're going to hear from him is a discussion about what government is doing to ensure all of our highest priority -- the protection of the American people," Lynch said in an interview on NBC's "Meet the Press."
The address, scheduled for 8 p.m. Eastern time, comes four days after a husband and wife killed 14 people and wounded 21 others in San Bernardino, California, and amid what Lynch reiterated was a continuing FBI investigation into the assailants' possible radicalization and their motivations.
"At this point we do not have any evidence that they were part of a larger group, or a cell, or were planning anything else," Lynch told NBC's Chuck Todd, referring to news media reports she said might be misleading.
"I would caution people not to try and define either of these individuals right now," she added.
The couple -- Tashfeen Malik, who was born in Pakistan, and Syed Rizwan Farook, who was born in the United States -- had stockpiled weapons, including pipe bombs, in their home before the shooting, which was the worst terrorist attack on U.S. soil since Sept. 11, 2001. Malik had pledged allegiance to the Islamic State, also known as ISIS, ISIL or Daesh, in a Facebook post. On Saturday during a radio broadcast, the group identified the couple as "supporters," a term viewed as further removed than members or operatives.
Lynch said that social media was playing a relatively small part in the larger terrorism investigation but said she could not discuss specific details of the case.
She urged individuals who notice a suspicious change in the behavior of friends or family members to contact law enforcement, but she said the standard for screening individuals should not necessarily be lowered.
In the speech, Obama is expected to reassure a nation on edge by resetting his emotional and rhetorical response to a massacre that investigators now believe was a homegrown terrorist attack inspired by the Islamic State.
The attacks in San Bernardino represent the first time that terrorists with suspected ties to the Islamic State have successfully struck the United States. And it comes in the wake of the deadly assault on multiple locations in Paris last month and the takedown of a Russian passenger jet over Egypt, both attributed to the Islamic State.
For Obama, the arrival of Islamic State-inspired terror in the United States underscores urgent questions about the military and diplomatic effort his administration initiated more than a year ago, when the terror group surged into Iraq, seizing territory there and in neighboring Syria.
The president has relied on airstrikes, financial sanctions and targeted special operations to counter the growth of the Islamic State, while building a diplomatic coalition of dozens of nations and resisting any call for the introduction of large numbers of U.S. ground troops in the Middle East.
Despite fierce bombings, the Islamic State militants continue to occupy large swaths of the region. And a sophisticated social media campaign by the group has succeeded in helping recruit across the globe, including, officials said, in the United States.
Obama is not expected to offer a new strategy. But in the speech, the president is likely to call for a more intense effort by the coalition to counter the terror group on the ground, and a renewed attempt to find a diplomatic solution to end the civil war in Syria.
For weeks, the president has sought to reassure Americans that they remain secure at home, while chiding politicians and others for giving in to fears stoked by the terrorists. In the days after the Paris attacks, Obama repeatedly urged people not to let fear of attacks turn them against Muslims or others in the country.
At the same time, Obama has sought to use the attack in San Bernardino, as he has used other recent mass shootings, to advocate for stricter gun laws in the United States. Initially, Obama's reaction to the deaths of 14 people in San Bernardino was similar to those he gave after shootings in Roseburg, Oregon, and Charleston, South Carolina -- somber, saddened and a reminder from him that gun restrictions were needed.
But once it became clear that this attack seemed different than the others, with a foreign and jihadi element, that response -- lacking any outrage or bellicosity -- may have seemed insufficient to his advisers.
Lynch, in her television appearance, called the recently passed USA Freedom Act, which limits some bulk data collection by U.S. intelligence agencies, a "good solution" -- but she argued that stricter gun control laws would help address violence in the country.
The attack, which was the focus of nearly all network talk shows Sunday morning, cast a shadow over a black-tie dinner at the State Department on Saturday night, where a mix of the political and artistic elite gathered to toast this year's recipients of the Kennedy Center Honors.
Secretary of State John Kerry, in an after-dinner speech, called the Islamic State's recent string of attacks an assault on "our shared cultural heritage," singling out the terrorist group's destruction of carefully preserved art, architecture, historic and holy sites in the Middle East.
"Some might not see the link between the destruction of culture and the attacks on human beings that Daesh has perpetrated in the Middle East, on the streets of Paris, in the skies over Egypt and elsewhere," Kerry said. "But make no mistake: These crimes are part of the same war on knowledge, on freedom, on creativity, on modernity, on law, on love, on life and on civilization itself."
Though Kerry did not mention the attack in San Bernardino by name, he offered a subtle reference to the importance of immigrants and refugees to U.S. culture and diplomacy.
"So tonight our message to terrorists everywhere is that no matter how many attacks you attempt, we will not be intimidated. We will not be divided. We will not abandon our values. We will not cease to celebrate beauty. We will not stop until we have stopped you," he said.
After the speech, Obama will travel a short distance to the Kennedy Center for the Kennedy Center Honors gala, which is being recorded for a future television broadcast. The White House had previously canceled the appearance, but said late Sunday afternoon that the president would attend after all.