President Obama, in the section of his State of the Union speech discussing ISIS, said something that American politicians don't usually say: that while ISIS "pose a direct threat to our people," they "do not threaten our national existence."
Here's the full quote, in context:
Priority number one is protecting the American people and going after terrorist networks. Both al Qaeda and now ISIL pose a direct threat to our people, because in today’s world, even a handful of terrorists who place no value on human life, including their own, can do a lot of damage. They use the Internet to poison the minds of individuals inside our country; they undermine our allies.
But as we focus on destroying ISIL, over-the-top claims that this is World War III just play into their hands. Masses of fighters on the back of pickup trucks and twisted souls plotting in apartments or garages pose an enormous danger to civilians and must be stopped. But they do not threaten our national existence. That’s the story ISIL wants to tell; that’s the kind of propaganda they use to recruit. We don’t need to build them up to show that we’re serious, nor do we need to push away vital allies in this fight by echoing the lie that ISIL is representative of one of the world’s largest religions. We just need to call them what they are — killers and fanatics who have to be rooted out, hunted down, and destroyed.
This cuts against the common portrayal of ISIS as a peril to the United States on part with the existential threats of past eras. A phrase you hear all the time in the American media — including from some Republican presidential candidates — is that ISIS poses an "existential threat" to the United States. That the group, or the ideology it stands for, could destroy the United States itself.
Obama is trying to undercut this narrative. While he admits that ISIS "can do a lot of damage," he's also correct that ISIS isn't capable of actually toppling the US; in fact, it's actually losing control of its own territory in Syria and Iraq. A group that can't fight off the Iraqi military and various Syrian rebel groups in its backyard simply doesn't have the firepower to pose a fundamental threat to the United States.
That's not to say that ISIS poses no danger to Americans — Obama is clear that it does — but rather appears intended to modulate American fears of ISIS that have perhaps, in his view, exceeded their actual threat.
While recent opinion polls show that terrorism is one of the American public's top issues, the fact is that terrorism actually only kills a tiny number of Americans per year (a number roughly comparable to the amount killed by their own furniture). Of course, such groups would like to kill many more Americans than that, and will continue trying to do that, but their actual toll is thankfully still far short of anything that can existentially threaten the US. ISIS is a danger, sure — but Obama is attempting to put the threat in its proper context.