President Obama said terrorism is an "evolving threat" but that the U.S. will be able to overcome it, speaking to the nation in a primetime address Sunday.
"The threat from terrorism is real, we will overcome it," Obama said. "We will destroy ISIL and any other organization that tries to harm us."
Obama's speech comes after a young Muslim couple killed 14 people in San Bernardino, California. The shooting, which the FBI is investigating as a terrorist attack, could be the deadliest terrorist attack on American soil since September 11, 2001.
Officials say the attackers were at least partially inspired by the terrorist group ISIS.
Obama called on lawmakers to pass gun control legislation and formally declare war against ISIS, which both face uphill battles in the Republican-led Congress.
While both are unlikely with the Republican-led Congress, the administration has worked with lawmakers on tightening security in the visa waiver program, which allows individuals with passports from 38 countries to travel to the United States without a formal visa.
The House will vote this week on a bill to add additional security requirements to that program.
The speech was the first time President Obama has addressed the nation from the Oval Office since the announcement of the end of U.S. combat operations in Iraq in August of 2010.