The vast majority of people trying to digest the news have no conception of radiation other than a negative impression. It is easy to verify this by asking people to say the first thing that comes to their mind when they see this:
It is invariably negative.
Compound that by the fact that there are so many technical terms and units used to describe various aspects of radiation and radioactivity, that unless you have had training in them, it is nearly impossible to put this stuff in context.
98% of the the people opining on this could not tell you (without consulting some website) what defines a millicurie or a becquerel, the difference between a rad, a rem and a sievert, a beta particle versus a gamma ray or how time, distance and shielding figure into the whole situation.
To complicate it even more, people don't have any context for radiation levels and danger to man. Throw all this together, multiply it by the factor of millions of people talking back and forth on the Internet, posting an article from one site, referencing another, often with no idea of the validity of the site, only that it came up in a Google search.
Add in the misquote of a radiation level in an article, move the decimal point one or two places either way, refer to an exposure level as millisieverts when it is microsieverts, and stir in a paucity of information from the area, and you have people who are terrified and scared.
I took the time to explain the concept of Potassium Iodide capsules to some folks on a thread, because I happen to know how they work because I gave them to people in the course of medical treatment. In response, I got a heartbreaking Freepmail from a woman in California: "...Thx very much for the posting. Im in nor california with kids and unable to get reliable info. Can u tell me if I should already be down in the basement? As the world turns, once around aren’t we plunging through contaminated atmosphere already? Where are u at? You taking any precautions? Im scared I need to keep kids out of school and board up the windows. Thx much for responding..."
I found this to be heartbreaking. This woman WAS terrified. Needlessly. If she lived in Japan within 50 miles of the reactors, that might be appropriate. But not in California.
A poster on this thread said you can be pro-nuclear and still be terrified of this situation. That is true, but you cannot be intelligent, properly informed and still be terrified of this particular situation.
Concerned? Absolutely. Terrified is an emotional response to this, not an intellectual response.