The bi-annual Unisys Security Index surveys more than 1,000 Americans to gauge consumer opinion on four areas of security: financial, national, Internet and personal safety. The total U.S. Unisys Security Index score jumped more than 20 percent over the past six months, to a level of concern that researchers marked as "serious" -- the first time the U.S. index reading has warranted that designation since the survey began in 2007.

The survey, taken in February, also showed that Americans are conflicted about government data leaks associated with the WikiLeaks web site, with many stating the site should be shut down and others asserting that leaks can help to keep government accountable to citizens.

On a scale of zero to 300, the Unisys Security Index stands at 164 in the US, up from 136 six months ago. The increase is due largely to higher concerns related to the war or terrorism, identity theft and bankcard fraud. For example, 70% of Americans surveyed said they were seriously concerned about identity theft, and 68% of Americans surveyed said they were seriously concerned about falling victim to credit or debit card fraud. Also, 67% were seriously concerned about national security.

"Recent events such as the WikiLeaks incident and some of the recent well-publicized hacker attacks may be pushing Americans to an inflection point in understanding just how critical the Internet is to all dimensions of security, whether securing our nation or securing our personal information," said Steve Vinsik, vice president, enterprise security, Unisys. "We believe that awareness levels will continue to rise as the Internet becomes more woven into all of our day-to-day lives."

Beyond Internet security, the new Unisys survey shows that Americans are just as concerned about potential security attacks on critical infrastructure targets as they are about transportation such as airplanes, airports and mass transit.

For example, 61 percent of Americans were seriously concerned about the vulnerability of bridges, power plants and pipelines -- a greater number than those seriously concerned about airport or airplane security (59 percent). Other areas of serious concern included mass transit (57 percent), large public gatherings (57 percent) and cargo (56 percent).

When asked about the recent WikiLeaks incident involving leaked classified U.S. government data, American respondents appeared to have mixed feelings on the issue. Nearly half (48 percent) of Americans surveyed were familiar with the WikiLeaks incident. Of those, 52 percent agreed "strongly" or "somewhat" with the statement that the release of the information was good and made the government accountable. However, 64 percent of Americans surveyed agreed with a statement that release of the information was harmful and that WikiLeaks should be shut down.

In addition, 73 percent of Americans surveyed who were familiar with the WikiLeaks incident expressed a lack of confidence in governments' ability to prevent future data leaks.