Calm down, America: We’re as safe as we were a year ago

President Obama hasn’t even given his speech outlining plans for increased military action to combat the Islamic State in Iraq and Syria, but we already have a chyron for its coverage: “America on Edge” is the way NBC headlined its new poll Tuesday, which found that 47 percent of Americans believe the U.S. is less safe than it was before the attacks of Sept. 11, 2001.

That’s higher than a year ago, when only 28 percent said we were less safe, and it’s higher still than in September, 2002, only...