She did this after forum host Matt Lauer brought up "terror attacks on our soil."

Lauer asked, "Would your message as the next President of the United States — or potential next president — be … that we are simply living in the reality that those attacks will happen? And can you guarantee people that, after four years of a Clinton presidency, they'll be safer on the streets of San Bernardino or Boston than they are today?"

Clinton responded by saying that she will "do everything in [her] power to make sure that that's the result." Then she added, "But I'm not going to promise something that I think most thinking Americans know is going to be a huge challenge." She tried to highlight the size of the challenge by focusing on what she sees as the necessity of an "intelligence surge" and efforts "to combat ISIS online, where they recruit." And she spoke of engaging ISIS in "the arena of ideas."