Last Updated Dec 16, 2015 4:12 PM EST
The public could be better-informed about potential terrorist threats, if changes to the Homeland Security Department alert system work as Secretary Jeh Johnson hopes they will.
"We are creating an intermediate level to the [National Threat Advisory System], that includes an NTAS bulletin which describes general developments or trends regarding threats of terrorism," Secretary Jeh Johnson told reporters.
The terror alert system, which was rolled out in 2011, had never been triggered because a credible terrorist threat was necessary to trigger an alert.
In conjunction with the announcement, DHS issued the first NTAS bulletin, which will be in effect through mid-June and can be found on DHS's website.
"We are in a new phase in the global terrorist threat, which has implications on the homeland, particularly with the rise and use of terrorist groups of the Internet to inspire and recruit. We are concerned about the self-radicalized actors who could strike with little or no notice," the first bulletin says, according to Johnson.
Johnson said the government is concerned not only about terrorist-directed, but also terrorist-inspired copy-cat-like attacks.
"The reality is terrorist-inspired individuals have conducted or attempted to conduct attacks in the United States this year," he said.
At the same time, Johnson said the U.S. has no intelligence about a specific or credible terrorist threat and that Americans shouldn't be afraid to live their daily lives normally.
"We urge the public to continue to travel, attend public events and freely associate with others, but remain vigilant," he said.
"What the Department of Homeland Security and the U.S. has to do is be able to convey to the public its sense of the threat," said CBS News Senior National Security Analyst Juan Zarate. "It's also signaling mechanism to state and local authorities who actually have to put police on the streets, security in the train stations, etcetera. It signals to them a bit more granularity."
Johnson reiterated and listed a number of other steps the government has taken, or is taking, to keep the homeland safe. Among other things, the Transportation Security Administration is in the process of improving aviation security and screening at airports. DHS, he added, is also reviewing the K-1 fiancee visa program, which the female San Bernardino used to travel to the U.S. from the Middle East.