The current National Terrorism Advisory System, begun in 2011, contains two levels. Elevated threat means there is a credible terrorist threat against the United States, while imminent threat refers to a more specific impending attack. That system, which replaced the frequently mocked five-color coded system put in place after the Sept. 11, 2001 attacks, has never been used.
Although Johnson ordered a review of the system earlier this year, he described the planned new intermediate level in language that made clear it could help warn against people such as the pair of gunmen who killed 14 people at a public health facility in San Bernardino. Although authorities said the rampage appeared to have been inspired by the Islamic State, the accused shooters — Tashfeen Malik and her husband, Syed Rizwan Farook — had not come to the attention of U.S. officials before the shootings.
The secretary said the United States is entering “a new phase in the global terrorist threat that involves not just terrorist directed attacks from overseas but also terrorist inspired attacks here on the homeland and in other countries.” In this environment, he said, “having not had a specific credible piece of intelligence reflecting a specific plot is not the end of the story because we’re dealing with the prospect of terrorist inspired attacks by someone who may be below our radar and who could act on a moment’s notice.”
Johnson said he hopes to announce the change soon and that he thinks it “reflects the current environment and current realities.”