Former Secretary of Homeland Security Michael Chertoff was on "Good Morning America" earlier Monday to discuss what the travel alert to Europe really means.
While he said that the travel alert is the "lowest level of warning that the State Department issues," Americans abroad should be mindful of their surroundings.
Among the useful and common sense tips he had for Americans who are abroad or going to be abroad was, first and foremost, to check exits in places and be vigilant. Also, he added, it might not be the best idea to walk around with a "big American flag on your backpack."
WATCH his interview with Robin Roberts below.