Besides the traditional Neighborhood Watch programs that encourage residents to keep an eye out for local crime, Americans are learning they need to be vigilant for global terrorism, too.

The September arrest of Najibullah Zazi stemmed, in part, from his purchase of a large quantity of beauty supply products from Denver area stores where a Colorado store clerk tipped off police about the suspicious activity. ...

The Major Cities Chiefs Association, formed by police chiefs in the largest cities in America and Canada, cited that clerk’s actions over the weekend as they endorsed the iWatch program as an easy way for citizens to combat terror.

Some groups warn, however, that these guidelines are too broad and could lead to the violation of people’s civil rights. For example, one of the suspicious activities is listed as wearing clothes too big or heavy for the weather. ...

Nevertheless, we are all a little wiser and a little more wary of the world around us with the terror of Sept. 11, 2001, still clear in our memory.

Vigilance might have been able to stop some 3,000 people from being brutally killed that day. ...

In the 21st century, Neighborhood Watch means more than calling authorities about suspicious activity on your street. It also means letting authorities know when you see the potential for terrorism. That’s a harsh reality, but it is the world we live in.