A partial government shutdown. A war in Iran. Warnings about sleeper cells. And in the middle of it all: Americans left to wonder if their travel plans are safe.
Those concerns were echoed in part by former Department of Homeland Security Secretary Jeh Johnson, who told CNBC the nation is operating in a "heightened security threat environment because of the fact that Iran is a state sponsor of terrorism."
Meanwhile, Transportation Security Administration officers charged with screening airline passengers for security threats are working without pay − another potential worry for air travel security.
Johnson didn't say travelers actually are at a higher risk. But he is among experts raising a number of concerns, including "lone actors inspired by terrorist organizations."
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