This is the part I found most significant:
Authorities believe the likelihood of terror attacks will continue as members of ISIL/Da’esh return from Syria and Iraq. Additionally, there is a continuing threat from unaffiliated persons planning attacks inspired by major terrorist organizations but conducted on an individual basis. Extremists have targeted large sporting events, theatres, open markets, and aviation services. In the past year, there have been multiple attacks in France, Nigeria, Denmark, Turkey, and Mali. ISIL/Da’esh has claimed responsibility for the bombing of a Russian airliner in Egypt.
Overly broad? Yes. Even a little panic-mongering? Maybe. But I don't disagree with any part of it. Both the range and the tempo of attacks on public venues have been increasing sharply, and successful attacks will lead to more attacks. Furthermore, successful tactics will lead to more of the same. We can reasonably expect to see more active shooter attacks and fewer car bombs, as extremist groups copy the tactics that worked in Mumbai, in Kenya's Westgate Mall, in Paris, and in Mali's Radisson Hotel.
I do not live my life in a constant state of fear, even when traveling in high threat locations, and I hope you won't either. That said, there is a time to be properly cautious. Even a time to defer going to large sporting events, theaters (or theatres), open markets, and on trains and planes.
To my fellow citizens living or traveling abroad, I quote the words of Kid Sally Palumbo's grandmother in the great comic novel The Gang That Couldn't Shoot Straight - "you watcha you ass."